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Polycarbonates (PC) are widely used as a high performance engineering plastics having an edge over other polymers for its impact, optical, tensile and thermal properties. PC, however, suffers to a drastic reduction in its impact properties at sub-zero temperature near the ductile-brittle-transition. Researchers have done extensive work on enhancing its property at low temperature and also studied the effect of modification on other important properties of PC. A substantial research work available in literature has been reviewed and PC properties, materials, basic approaches for property enhancement, characterization methods etc. have been discussed. The conventional methods like blending and copolymerization, and recently developed methods like nano-addition and reactive blending for property enhancement have been reviewed [ABSTRACT FROM AUTHOR]

AbstractNanocomposites (NC) of amorphous polycarbonate (PC) and cerium oxide (CeO2) nanoparticles (NPs) were prepared. The synthesized CeO2 had a nanonature of average particle size 22 nm, as indicated from their high resolution transmission electron microscopy images (HTEM). Samples of the PC/CeO2 NC films were irradiated with several γ ray doses (10-80 kGy). The resultant outcome of the γ irradiation on the optical properties of the NC films was studied using ultraviolet spectroscopy (UV-vis). Upon raising the γ ray dose up to 80 kGy, the maximum dose used, the direct bandgap decreased from 4.92 to 3.91 eV. The Urbach energy showed an opposite trend; it increased from 0.46 to 0.92 eV. This could be attributed to the domination of chain crosslinks. Also, the optical dielectric loss (ε”) assisted in identifying the nature of the microelectronic transitions. It was found that the PC/CeO2 NC films had direct allowed transitions. Additionally, the γ induced changes in the optical conductivity were studied. Moreover, the optical color changes between the pristine and the irradiated films were evaluated. The pristine NC film was uncolored. It showed significant color changes when irradiated with γ radiation up to 80 kGy. The induced modifications in the optical properties suggest that the γ radiation is an effective means for modifying the properties that allows the use of PC/CeO2 NC in optoelectronic devices. [ABSTRACT FROM AUTHOR]

There is growing interest in metrics for developing circular and sustainable products. Life Cycle Assessment (LCA) and the Material Circularity Indicator (MCI) are prominent for analyzing environmental performance and product circularity, respectively. This study compares these methodologies applied to a case of plastic parts made from virgin Polycarbonate + 10% Fiber Glass for smart electricity meters. Sensitivity analyses were conducted on the recycled content used and the final treatment of parts. Both methodologies are sensitive to recycled content usage. The best scenario (SA1-10) features 100% recycled content and full recycling of parts, while the worst scenario (SA2-1) uses 100% virgin content with all parts disposed of in landfills. The results highlight similarities and differences between the methodologies. MCI focuses on material source, life extension, and end-of-life treatment to measure circularity. LCA covers a broader range of impact categories, including resource use, human health, and ecosystem impacts, making it more comprehensive for environmental analysis. Both emphasize the importance of recycled content and end-of-life treatment, underscoring the benefits of recycling in reducing environmental impacts and enhancing circularity. [ABSTRACT FROM AUTHOR]

Copyright of China Plastics / Zhongguo Suliao is the property of Journal Office of CHINA PLASTICS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study delves into optimizing production parameters and 3D printing (3Dp) conditions for alkaline‐treated 10% hemp fiber‐reinforced polycarbonate (PC) composites. Initially, composite filaments were extruded at 250°C (PCH250) and 230°C (PCH230) to assess the impact of varying melt mixing temperatures on thermal behavior. Thermal characterization was conducted using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). DSC analysis indicated consistent glass transition temperatures (Tg) across pure PC and the composites, while TGA revealed minimal thermal degradation in PCH230 compared to pure PC. Subsequently, to ascertain the optimal 3D printing temperature, specimens were printed at temperatures elevated by 10°C relative to their melt mixing temperatures (PCH250/260 and PCH230/240), followed by mechanical evaluation via tensile testing. PCH230/240 exhibited superior mechanical properties, demonstrating a 12% increase in tensile strength and a 29% increase in Young's modulus compared to pure PC. Additional testing at 230°C printing temperature (PCH230/230) demonstrated enhanced mechanical strength over PCH250/260 but inferior performance relative to PCH230/240, attributed to incomplete interlayer adhesion observed through SEM analysis. Consequently, the optimal composite melt mixing temperature was determined to be 230°C, with an accompanying 3D printing temperature of 240°C for optimal mechanical performance. Highlights: 3D printable, 5% NaOH treated hemp fiber reinforced polycarbonate composite.Printing composite with 3D printing device at different temperatures230°C process temperature gives the best thermal properties.240°C 3Dp temperature provides the best mechanical and morphological properties. [ABSTRACT FROM AUTHOR]

Interfacial bond formation during sputter deposition of metal‐oxide thin films onto polycarbonate (PC) is investigated by ab initio molecular dynamics simulations and X‐ray photoelectron spectroscopy (XPS) analysis of PC|X interfaces (X = Al2O3, TiO2, TiAlO2). Generally, the predicted bond formation is consistent with the experimental data. For all three interfaces, the majority of bonds identified by XPS are (C─O)─metal bonds, whereas C─metal bonds are the minority. Compared to the PC|Al2O3 interface, the PC|TiO2 and PC|TiAlO2 interfaces exhibit a reduction in the measured interfacial bond density by 75 and ∼65%, respectively. Multiplying the predicted bond strength with the corresponding experimentally determined interfacial bond density shows that Al2O3 exhibits the strongest interface with PC, while TiO2 and TiAlO2 exhibit ∼70 and ∼60% weaker interfaces, respectively. This can be understood by considering the complex interplay between the metal‐oxide composition, the bond strength, and the population of bonds formed across the interface. [ABSTRACT FROM AUTHOR]

The increased rate of postuse accumulation of the heteroatom‐containing plastic wastes, like polyethylene terephthalate (PET), polycarbonate (PC) and polyurethane (PU), in the environment propels the research for effective and sustainable valorization. In this study, PET from bottle waste, PC from compact discs, and PU from waste wind turbine blade were characterized and employed for fast pyrolysis experiments. Importantly, red mud (RM), a mixed oxide rich in Fe, Al, Si, Na, and Ca, was used as a catalyst for fast pyrolysis. The effects of temperature and feed/catalyst ratio on product yields were studied to elucidate the product formation mechanism. Benzoic acid and its derivatives, bisphenol‐A and oxygenated aromatics, and 4,4′‐methylenebisbenzamine were the major products obtained from the noncatalytic fast pyrolysis of PET, PC, and PU, respectively. The use of RM improved the yield of aromatic hydrocarbons from PET to 27.8 wt% at 550 °C, phenolics from PC to 46.6 wt% at 550  °C, and 4,4′‐methylenebisbenzamine to 34.9 wt% at 650 °C. The catalytic activity of RM is ascribed to the presence of active basic sites. The present study paves the path for the catalytic upcycling of challenging plastic wastes using industrial waste, like RM, as a sustainable catalyst from a circular economy viewpoint. [ABSTRACT FROM AUTHOR]

In initial experiments the effects of aromatic model substances on carbon nanotube (CNT) dispersions in dimethylformamide (DMF) were investigated. Electron‐deficient aromatics interact strongly with CNTs, causing increased agglomeration and sedimentation. Conversely, electron‐donating aromatics stabilize CNT dispersions in DMF. Polymers with electron‐deficient aromatics, such as polydinitrostyrene (PDNS), exhibit a concentration‐dependent effect: low concentrations lead to stabilization of dispersions, while higher concentrations lead to sedimentation. This suggests that such polymers can enhance attraction between the matrix of CNT‐reinforced polymers as well as stabilize the dispersed CNTs. Polycarbonate, modified with polydinitrocarbonate (PDNC) and reinforced with CNTs showed improved mechanical properties. The addition of 6 wt.% CNTs and 6 wt.% PDNC resulted in a notable improvement with a 22% increase in tensile strength, a 29% increase in flexural strength, a 39% increase in Young's modulus and a 47% increase in flexural modulus. This enhancement resulted in an overall mechanical performance comparable to the high‐performance polymer polyetherimide. However, there must be noted, that the addition of PDNC increases the CNT particle size, which can negatively affect mechanical properties. The results highlight the additive's dual role in enhancing adhesive interactions while potentially increasing CNT agglomerate sizes. Highlights: Interactions of CNTs dispersed in DMF and various aromatics were investigated.Polydinitrocarbonate (PDNC) was synthesized as a new additive for CNT‐composites.Polycarbonate/CNT‐composites were obtained using extrusion.Test specimens with CNT contents up to 6 wt.% were obtained.Mechanical properties of polycarbonate reached the level of polyetherimide. [ABSTRACT FROM AUTHOR]

This investigation explores the permeation characteristics of hydrogen (H 2), carbon dioxide (CO 2), and oxygen (O 2) using metal oxide@g-C 3 N 4 /polycarbonate (M@CN/PC) membranes. This study involves the testing of various metals, namely lithium (Li), magnesium (Mg), and silicon (Si), with different filler percentages of M@g-C 3 N 4 (3% and 10%). The permeability assessments were carried out at room temperature under a 40 psi pressure. The characterization of fillers and membranes was conducted using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and differential scanning calorimetry (DSC). Furthermore, we have also measured the permeability of H 2 , CO 2 , and O 2 , and evaluated the selectivity ratios of H 2 /CO 2 , H 2 /O 2 , and CO 2 /O 2. Both permeability and selectivity were found to increase with M@CN content. [Display omitted] • Metal oxide-doped g-C 3 N 4 /PC membranes synergistically boost gas permeability and selectivity as compared to neat PC membranes. • In the present study, metal-doped fillers were used for achieving a balance between gas permeability and selectivity. • The synthesis of metal oxide-doped g-C 3 N 4 /PC membranes with metal-doped fillers employed phase inversion techniques. [ABSTRACT FROM AUTHOR]

In the last two decades, a great interest has been focused on the creation and study of superhydrophobic nanomaterials based on the "lotus effect." This effect is caused by the heterogeneous wetting of rough surfaces, when the grooves of a rough surface are filled with air (vapor) and water contacts only with the tops of the protrusions. A drop forms a sphere on the surface and rolls down picking up dirt particles when the surface is slightly tilted. Diverse methods have been developed for producing such materials, and the potential of the ion-track technology (ITT) is being investigated. The goal of this work is to study the wettability of surface microtextures by the examples of two materials with different initial degrees of hydrophobicity. The ITT has been employed to obtain samples with maximum water contact angles of 140 ± 5° and 151 ± 5° by modifying the surfaces of polycarbonate and polypropylene films, respectively. It has been shown that such angles are characteristic of microtextures, for which surface fraction f that is in contact with a droplet is decreased to a range of 0 < f < 0.3. Materials with tilted microtextures have been obtained in order to increase the probability of droplet rolling down a material surface in a certain direction. In this case, the wettability becomes anisotropic. A droplet loses its spherical shape and is deformed in the direction of the tilt of needle-like surface elements. It has been found that the anisotropy of wettability is higher at a tilt angle of the texture elements of 45° than that at 30° (relative to the flat surface). [ABSTRACT FROM AUTHOR]

The processing conditions were varied during the production of polycarbonate-based composites with the multiwalled carbon nanotubes (MWCNTs) Baytubes® C150 P (Bayer MaterialScience AG, Leverkusen, Germany), by melt mixing with an extruder on a laboratory scale. These included the screw design, rotation speed, throughput, feeding position and MWCNT content. Particular attention was paid to the shortening of the MWCNT length as a function of the conditions mentioned. It was found that there is a correlation between the applied specific mechanical energy (SME) during the melt mixing process and MWCNT dispersion, which was quantified by the agglomerate area ratio of the non-dispersed nanotubes based on optical microscopic analysis. The higher the SME value, the lower this ratio, which indicates better dispersion. Above an SME value of about 0.4 kWh/kg, no further improvement in dispersion was achieved. The MWCNT length, as measured by the quantitative analysis of TEM images of the MWCNTs dissolved from the composites, decreased with the SME value down to values of 44% of the original MWCNT length. At a constant loading of 3 wt.%, the tensile strength and tensile modulus were almost independent of the SME, while the elongation at break and notched impact strength showed an increasing trend. The variation in the feeding position showed that feeding the MWCNTs into a side feeder led to slightly better electrical and mechanical properties for both types of MWCNTs studied (Baytubes® C150 P and Nanocyl™ NC7000 (Nanocyl S.A., Sambreville, Belgium)). However, feeding into the hopper led to better CNT dispersion with Baytubes® C150 P, while this was the case with Nanocyl™ NC7000 when feeding into the side feeder. The screw profile had an influence on the dispersion, the MWCNT length and the electrical resistance, but only to a small extent. Distributive screws led to a greater shortening of the MWCNT length than dispersive screws. By varying the MWCNT content, it was shown that a greater MWCNT shortening occurred at higher loadings. Two-stage masterbatch dilution leads to stronger shortening than composite production with direct MWCNT incorporation. [ABSTRACT FROM AUTHOR]

The combination of the best properties of Polycarbonate (PC) and Acrylonitrile-butadiene-styrene (ABS) has resulted in the development of commercially available PC/ABS blends that have been found to be useful in many molding applications. PC has excellent mechanical and optical properties, but predominant use of bisphenol A in PC synthesis raises concerns regarding its potential environmental harm. In this study, we have studied the alternative for the PC/ABS blend by replacing PC with the bio-based PC and ABS with the Acrylonitrile-styrene-acrylate (ASA). A blend of bio-based PC and ASA was prepared by the melt blending techniques and investigated mechanical, thermal, and degradation (hydrolytic and soil burial degradation) properties. [ABSTRACT FROM AUTHOR]

The recent emphasis on nanocomposites composed of polymers and metal oxides is largely due to their significant promise as effective radiation sensors, detectors, and dosimeters for gamma rays, X-rays, and charged particles. The sensitivity of a system may be affected by various factors, including the volume of the sensitive material, the concentration of heavy metal oxide nanoparticles, the bias voltage applied, and the degree of crystallinity within the polymer matrix. Studies have shown that a pronounced degree of crystallinity in polymers can restrict the homogeneous spread of nanoparticles. This research utilized two distinct polymer matrices, namely HDPE and PC, to create a nanocomposite that incorporated bismuth oxide nanoparticles at concentrations reaching 60 wt%. FESEM images revealed that PC exhibited better dispersion up to 60 wt%, while HDPE showed agglomeration at 40 wt%. Under a defined dose rate of 42.67 mGy.min-1, and with a fixed amount of Bi2O3 nanofillers, the dosimetry response (measured as a change in electrical current) of PC was twice as pronounced compared to HDPE. Therefore, PC, as an amorphous polymer containing 50 wt% Bi2O3, may be considered a suitable candidate for dosimetry applications. [ABSTRACT FROM AUTHOR]

A PPC‐dodecyl glucoside (PPC‐APG) polymer was synthesized by the terpolymerization of carbon dioxide (CO2), propylene oxide (PO), and the bio‐based monomer APG for the first time. The thermal stability and mechanical properties of PPC‐APG were significantly improved compared with those of conventional polypropylene carbonate (PPC), and its glass transition temperature (Tg) was increased by 14°C compared with that of PPC. The 5% heat loss temperature (Td,−5%) and total heat loss temperature (Td,max) of PPC‐APG were increased by 89.1 and 92.1°C, respectively, compared with those of PPC. The tensile strength of PPC‐APG was increased to 25.6 MPa, its elongation at break was decreased to 125.1%, and its thermal elongation and permanent deformation were reduced to 97.2% and 62.9%, respectively, which improved the processability of the material. In addition, the introduction of bio‐based monomers also rendered PPC‐APG functional, and its surface tension reached a maximum of 61.3 mN/m at a concentration of 0.05 g/mL, with a good degradability. The higher surface tension and enhanced degradability of PPC‐APG indicate its potential for application as a plastic printing substrate. [ABSTRACT FROM AUTHOR]

Compatibility of polycarbonate (PC) and polymethyl methacrylate (PMMA) alloys was improved by using a transesterification catalyst (SnCl2·2H2O). Modified PC/PMMA alloys exhibit single Tg, and their initial island phase existing in the SEM were transformed into uniform surface. Besides, the transmittance of the modified alloys was increased from original 40% to 85%. Moreover, PC/PMMA alloys and PC foams with micro‐cellular and nano‐cellular structures were prepared by solid‐state CO2 foaming in the presence of transesterification catalyst. Distinctively, there are obvious nano‐cellular structures existing in the PC samples, but no related nanostructures were found in PMMA samples, after treated by same amount of catalyst and foaming process for pure PC and PMMA matrix. Furthermore, the effects of foaming temperature and segment structure on their foaming behavior were also studied. Additionally, a uniaxial stress experiment was conducted at a specific temperature to simulate the biaxial stress during the foaming process for discovering the mechanism of nanopore formation. Therefore, the concept of nano‐cellular structures will point out a direction for the development of high‐performance, heat insulation PC materials of the next generation. Highlights: Transesterification catalysts enhanced compatibility between PC and PMMA.Nanopore structures were successfully constructed in PC foams.Segment stretching was the main reason for the formation of nanopores. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

AbstractA nanocomposite (NC) of polycarbonate (PC), poly(methyl methacrylate) (PMMA), polyethylene oxide (PEO) and cadmium selenide (CdSe) nanoparticles (NP) was prepared using thermolysis and ex-situ casting techniques. The microstructure and shape of the CdSe NP were characterized with the Rietveld methodology and transmission electron microscopy (TEM). Rietveld refinement of x-ray data indicated that the prepared CdSe NP had the cubic zinc blend structure with a lattice parameter of 6.057 Å. TEM images showed the formation of a dotted shape of CdSe with a particle size around 2 nm, confirming the quantum dot size of the mother phase CdSe. Samples from the prepared PC/PMMA/PEO/CdSe NC films were irradiated with γ ray doses ranging from 5 to 80 kGy. We used UV-vis spectroscopy to investigate the resultant effects of the γ ray irradiation on the optical properties of the prepared films. The effect of the γ ray irradiation on the light absorbance, extinction coefficient, refractive index and optical conductivity of the PC/PMMA/PEO/CdSe NC films was studied. The absorbance of the NC films increased as they were irradiated with the γ ray doses up to 80 kGy, the maximum dose used. The increase in absorbance was accompanied with a decrease in the direct bandgap, from 5.31 to 4.05 eV, and an increase of Urbach energy from 0.44 to 0.89 eV. Also, we used the optical dielectric loss (ε”) to identify the type of microelectronic transition for the PC/PMMA/PEO/CdSe NC films, which was found to be a direct allowed transition. Furthermore, the optical color changes between the pristine and the irradiated films were evaluated using the International Commission on Illumination (CIE) color differences technique. The pristine film was uncolored. It showed significant color alterations when irradiated with γ radiation up to 80 kGy, the maximum dose used. [ABSTRACT FROM AUTHOR]

This study focuses on the experimental investigation of the mechanical properties of PBT/PC blends with varying compositions. The studied mechanical properties include tensile strength, elongation, tensile modulus, impact strength, and Shore hardness of PBT/PC blends with different PC contents. PBT, characterized by its semi‐crystalline and tough nature, contrasts with PC, known for its impact resistance and hardness. Achieving an optimal blend composition proves to be crucial for attaining the best combination of these properties. The tensile strength of the PBT/PC 30/70 blend increased by approximately 24%, with Shore hardness also experienced a 12% enhancement compared to pure PBT. This improvement is attributed to the presence of PC segments in the blend structure. Conversely, an increase in PC content led to the elongation and impact strength of the blends peaking in the PBT/PC 70/30 blend. Notably, the impact strength of the PBT/PC blend with 30% PC increased by about three times compared to PBT and 18% more than pure PC. Scanning Electron Microscopy (SEM) analysis revealed that PBT and PC segments disperse at lower PC content, while at higher content, phase separation becomes prominent. Fourier Transform Infrared Spectroscopy (FTIR) analysis indicates direct transesterification between PBT and PC, resulting in the formation of a long‐chain blend structure with random copolymer blocks. The transesterification mechanism is also supported by Differential Scanning Calorimetry (DSC) results, wherein a reduction in the crystallization temperature (Tc) and an increase in the glass transition temperature (Tg) is observed. The study concludes that the volume of these segments and their bonding play a decisive role in determining the mechanical properties. The bonding mechanism elucidated through FTIR and SEM provides valuable insights into the fabrication and property engineering of PBT/PC blends. [ABSTRACT FROM AUTHOR]

The integration of compatibilisers with thermoplastics has revolutionised the field of polymer composites, enhancing their mechanical, thermal, and rheological properties. This study investigates the synergistic effects of incorporating SEBS-g-MAH on the mechanical, thermal, and rheological properties of polycarbonate/acrylonitrile-butadiene-styrene/graphene oxide (PC/ABS/GO) (PAGO) and the properties of polycarbonate/acrylonitrile-butadiene-styrene/graphene oxide (PC/ABS/rGO) (PArGO) composites through the melt blending method. The synergistic effects on thermal stability and processability were analysed by using thermogravimetry (TGA), melt flow index (MFI), and Fourier-transform infrared spectroscopy (FTIR). The addition of SEBS-g-MAH improved the elongation at break (EB) of PAGO and PArGO up to 33% and 73%, respectively, compared to the uncompatibilised composites. The impact strength of PAGO was synergistically enhanced by 75% with the incorporation of 5 phr SEBS-g-MAH. A thermal analysis revealed that SEBS-g-MAH improved the thermal stability of the composites, with an increase in the degradation temperature (T80%) of up to 17% for PAGO at 1 phr SEBS-g-MAH loading. The compatibilising effect of SEBS-g-MAH was confirmed by FTIR analysis, which indicated interactions between the maleic anhydride groups and the PC/ABS matrix and GO/rGO fillers. The rheological measurements showed that the incorporation of SEBS-g-MAH enhanced the melt flowability (MFI) of the composites, with a maximum increase of 38% observed for PC/ABS. These results demonstrate the potential of SEBS-g-MAH as a compatibiliser for improving the unnotched impact strength (mechanical), thermal, and rheological properties of PC/ABS/GO and PC/ABS/rGO composites, achieving a synergistic effect. [ABSTRACT FROM AUTHOR]

AbstractIn order to find an optimal antibacterial agent for Polycarbonate (PC), five quaternary fluoroalkyl phosphonium salts (FAPS) with iodine anions (PPICF-13), tetrafluoroborate (FB-PPCF-13), trifluoromethanesulfonate (TFMS-PPCF-13), methanesulfonate (MS-PPCF-13), and p-toluenesulfonate (pTS-PPCF-13), each with a side chain of 13 fluorine atoms, were incorporated were incorporated into PC with a mass ratio of 2.5 wt.%. The influence of the counter anions on the rheological properties, mechanical properties, appearance and light transmittance, antibacterial activity and cytotoxicity of the antibacterial PCs were investigated. The results showed that all the FAPS could impart PC with above 90% of antibacterial degree. The melt flow rate of the PC was increased due to the plasticizing effect of FAPS. The incorporation of up to 2.5 wt.% FAPS had no negative influence on the flexural strength, flexural modulus and tensile strength of the PC, but reduced the impact strength of the PC to varying degrees, depending on the counter anion. All five of the FAPS influenced the appearance and light transmittance of PC, and the TFMS-PPCF-13, MS-PPCF-13 and pTS-PPCF-13 samples appeared to have less impact on these properties than PPICF-13 and FB-PPCF-13. All antibacterial PCs; except for the antibacterial PC containing PPICF-13, exhibited no cytotoxicity. Considering all the properties, the antibacterial PC containing TFMS-PPCF-13 showed the optimal comprehensive properties based on this research. [ABSTRACT FROM AUTHOR]

Introduction: Additive manufacturing (AM) is a revolutionary technology transforming traditional production processes by providing exceptional mechanical characteristics. Methods: The present study aims explicitly to predict the hardness of Polycarbonate (PC) parts produced using AM. The objectives of this study are: (1) To investigate the process parameters that impact the ability to estimate the hardness of PC materials accurately, and (2) To develop a best-performing ML model from a range of models that can reliably predict the hardness of additively manufactured PC parts. Initially, fused filament fabrication (FFF), the most affordable AM technique, was used for the manufacturing of parts. Four process parameters, infill density, print direction, raster angle, and layer thickness, are selected for investigation. A heatmap is generated to obtain the influence of process parameters on hardness. Then, machine learning (ML) techniques create a range of predictive models that can predict hardness value considering the level of process parameters. Results: The developed ML models include Linear Regression, Decision Tree, Random Forest, K-nearest neighbor, Support Vector Regression, AdaBoost, and Artificial Neural Network. Further, an investigation has been done that includes choosing and improving ML algorithms and assessing the models' performance. Discussion: Prediction plots, residual plots, and evaluation metrics plots are prepared to gauge the performance of the developed models. Thus, the research enhances AM capabilities by applying predictive modeling to process parameters and improving the quality and reliability of fabricated components. [ABSTRACT FROM AUTHOR]

AbstractTo further improve the comprehensive properties of polycarbonate/acrylonitrile–butadiene–styrene terpolymer blends (PC/ABS), in this work, styrene–acrylonitrile copolymer [P(St-co-An)] was grafted on the surface of attapulgite particles (ATP) by simultaneous reverse and normal initiation ATRP (SR&NI ATRP) to yield ATP@P(St-co-An) hybrid particles. Then a series of PC/ABS/ATP@P(St-co-An) composites were prepared via the melt blending method. The effects of ATP@P(St-co-An) content on the morphological, mechanical, thermal and rheological properties of the composites were investigated in detail. The core-shell ATP@P(St-co-An) hybrid particles with the polymer layer thickness of 20-40 nm were synthesized successfully according to the results of X-ray photoelectron spectrometer (XPS), Fourier transform infrared spectrometer (FTIR), gel permeation chromatography (GPC), thermogravimetric analysis (TGA) and transmission electron microscopy (TEM). The improvement in mechanical properties, reduced glass transition temperature (Tg) difference between PC and ABS and micromorphology changes of the composites proved the compatibilization, strengthening, and toughening effect of the ATP@P(St-co-An). Compared with the PC/ABS blend, with strength and toughness of 50.8 MPa and 56.3 kJ/m2, when the ATP@P(St-co-An) content was 4 wt%, a reasonable balance (85.8 MPa and 86.2 kJ/m2) between strength and toughness was achieved with substantially enhanced thermal stability. Moreover, the composite showed more remarkable non-Newtonian behavior, and its processability was also improved. We believe this work provides an effective approach to optimize the compatibility and comprehensive properties of PC/ABS blends. [ABSTRACT FROM AUTHOR]

We prepared yttria‐stabilized zirconia (YSZ) and titania crystalline thin films on polycarbonate (PC) substrates by the sol‐gel transfer technique that we have developed recently. Precursor gel films were deposited by spin‐coating on a polyimide/polyvinylpyrrolidone mixture layer on Si(100) substrates, and then were calcined at 600°C. The spin‐coating and the calcination were cycled, followed by final firing at 600–1000°C, to obtain 140–190 nm thick, YSZ and titania crystalline thin films. The film densification progressed as the final firing temperature increased, where the porosity calculated from the refractive index decreased down to a few percent. The film thus obtained was heated at 190°C on a hot plate, and a PC substrate was pressed on the film to transfer it to the PC substrate. The transferability quantified by image analysis of the film area was found to be significantly different between the YSZ and titania films. In the case of YSZ films, the area of silicon that was fractured and adhered to the transferred film increased significantly with increasing firing temperature, leading to a decrease down to 0% in the fraction of the successful transfer area without such a damage. On the other hand, the fraction of the successful transfer area remained around 90% irrespective of the firing temperature for the titania films. The surface of the titania films that were fired at 800–1000°C and transferred to PC substrates had voids of several tens nm scale, which may have been formed during anatase‐to‐rutile phase transformation. We thought that the reduced titania/Si(100) contact area due to such void formation facilitated the delamination of the titania films from Si(100) substrates. High temperature firing, which promotes crystallization and densification of films, thus affects differently the film transferability to plastic substrates, depending on the type of films. The work also suggested possible use of titania films as release‐assisting layers. [ABSTRACT FROM AUTHOR]

Thermoplastic (TP) composites, known for their ease of handling, suitability for high production rates, and recyclability, are emerging as a promising alternative to thermoset-based composites. The expected growth in TP-based composites in automotive, sports, and aerospace industries may result in increased post industrial waste. To address this, we repurposed our in-house process scrapped carbon fibre-reinforced polycarbonate tapes into sheet moulding compounds (SMCs) and Hybridised SMCs (Hy-SMCs) using compression moulding. In Hy-SMCs, the top and bottom layers were unidirectional tapes, while the core section had randomly oriented platelets in a 50:50 ratio. Our evaluation included qualitative and thermo-mechanical standard tests. The incorporation of unidirectional tapes in Hy-SMCs significantly improved the tensile and flexural properties of SMCs. Specifically, these enhancements resulted in an impressive 81 to 85% increase in mechanical strength compared to the standard aluminium grade. Additionally, Hy-SMCs exhibited a 120 to 130% increase in tensile and flexural properties compared to SMCs. Fractography revealed a complex relation between fractured surfaces, with multimode failures in both SMCs and Hy-SMCs. Also, the non-destructive evaluation showed platelet reorientation during consolidation and localised voids with increased specimen thickness. [ABSTRACT FROM AUTHOR]

Intratumor microbes have attracted great attention in cancer research due to its influence on the tumorigenesis, progression and metastasis of cancer. However, the therapeutic strategies targeting intratumoral microbes are still in their infancy. Specific microorganisms, such as Fusobacterium nucleatum (F. nucleatum), are abundant in various cancer and always result in the CRC progression and chemotherapy resistance. Here, a combined anticancer and antibacterial therapeutic strategy is proposed to deliver antitumor drug to the tumors containing intratumor microbiota by the antibacerial polymeric drug carriers. We construct oral tellurium-containing drug carriers using a complex of tellurium-containing polycarbonate with cisplatin (PTE@CDDP). The results show that the particle size of the prepared nanoparticles could be maintained at about 105 nm in the digestive system environment, which is in line with the optimal particle size of oral nanomedicine. In vitro mechanism study indicates that the tellurium-containing polymers are highly effective in killing F.nucleatum through a membrane disruption mechanism. The pharmacokinetic experiments confirmed that PTE@CDDP has the potential function of enhancing the oral bioavailability of cisplatin. Both in vitro and in vivo studies show that PTE@CDDP could inhibit intratumor F.nucleatum and lead to a reduction in cell proliferation and inflammation in the tumor site. Together, the study identifies that the CDDP-loaded tellurium-containing nanoparticles have great potential for treating the F.nucleatum -promoted colorectal cancer (CRC) by combining intratumor microbiota modulation and chemotherapy. The synergistic therapeutic strategy provide new insight into treating various cancers combined with bacterial infection. The synthesized antibacterial polymer was first employed to remodel the intratumor microbes in tumor microenvironment (TME). Moreover, it was the first report of tellurium-containing polymers against F.nucleatum and employed for treatment of the CRC. A convenient oral dosage form of cisplatin (CDDP)-loaded tellurium-containing nanoparticles (PTE@CDDP) was adopted here, and the synergistic antibacterial/chemotherapy effect occurred. The PTE@CDDP could quickly and completely eliminate F.nucleatum in a safe dose. In the CRC model, PTE@CDDP effectively reversed the inflammation level and even restored the intestinal barrier damaged by F.nucleatum. The ultrasensitive ROS-responsiveness of PTE@CDDP triggered the fast oxidation and efficient drug release of CDDP and thus a highly efficient apoptosis of the tumors. Therefore, the tellurium-containing polymers are expected to serve as novel antibacterial agents in vivo and have great potential in the F.nucleatum -associated cancers. The achievements provided new insight into treating CRC and other cancers combined with bacterial infection. [Display omitted] [ABSTRACT FROM AUTHOR]

Copyright of Polymer Materials Science & Engineering is the property of Sichuan University, Polymer Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article presents the results of numerical simulation of the technological parameters of the process of milling polycarbonate workpieces at different combinations of cutter tooth spacing, cutting depth, and cutting speed with and without using ultrasonic vibrations. The influence of cutter tooth spacing and milling mode features on the technological parameters of the process, including friction and cutting forces and temperature, is established. Using ultrasonic vibrations achieves a decrease in the main component of the cutting force and in the average and maximum temperatures in the chip-tooth and tooth-workpiece contact areas. [ABSTRACT FROM AUTHOR]

Conductive fillers‐embedded plastic polymer hybrid composites are crucial electronic materials in modern technologies owing to their tunable conductive properties, low density, and corrosion resistance. However, the application of traditional rigid inorganic conductive fillers‐embedded plastic composites is constrained by their subpar electrical conductivity and mechanical properties. Consequently, liquid metals (LMs) including gallium and gallium‐based alloys, have recently emerged as the preferred conductive flexible fillers over traditional rigid fillers. This work employs a solvent evaporation method and phase separation‐induced conductivity mechanism. The resulting flexible and electrically conductive LM‐polycarbonate (PC) film circuits demonstrate ultrahigh metallic conductivity, robust mechanical performance, excellent solvent recyclability, and notable processability. The fluidic nature of LMs and the superior mechanical properties of the PC polymer confer high electrical stability and durability to the LM‐PC film circuits under diverse mechanical forces and environmental conditions. The LM‐PC film circuits are exceedingly promising and apt for use as flexible conductors in contemporary electrical applications, including electricity transmission and underwater working. [ABSTRACT FROM AUTHOR]

This paper is devoted to estimating the effect of coloring (RAL 7037) polycarbonate and polysulfone with different yellowness indices on a complex of optical, physicomechanical, and rheological properties. It is shown that the introduction of color additives into heat-resistant polymers does not radically change their principal rheological and physicomechanical properties and does not require any modification for the methods and conditions of their processing. [ABSTRACT FROM AUTHOR]

This article presents experimental research conducted on polycarbonate sheets deformed via single-point incremental forming (SPIF). Building upon established frameworks from previous studies, the analysis focuses on evaluating the formability and failure modes, particularly necking and fracture, of polymeric sheets in both conventional and incremental forming processes. The experimental design encompasses an investigation of spindle speed and step down process parameters, utilizing both oil and water as lubricants, to comprehensively assess their effects. The findings provide insights into how these parameters influence formability and affect the failure mode. When using oil as a lubricant, three distinct failure modes were observed during deformation: fracture, twisting, and crazing. An increased twisting was associated with higher step down values, whereas elevated spindle speeds contributed to increase crazing. Additionally, these tests revealed a “post-crazing” failure mode following deformation. Conversely, when water was used as a lubricant, only fracture and twisting were observed in the SPIF specimens. This work introduces, for the first time ever, a complete investigation of these failure modes through scanning electron microscopy analysis of the failure surface. This analysis scrutinizes surface features and interprets them, thus providing a valuable tool for failure analysis.

Abstract Catalytic hydrogenolysis systems of C-O bonds in furan ring, tetrahydrofuran ring and tetrahydropyran ring in biomass-derived cyclic compounds are reviewed. Furfural or its hydrogenation products (furfuryl alcohol and tetrahydrofurfuryl alcohol) have been frequently used as substrates for this type of reactions. Ring-opening of furfuryl alcohol over metal catalysts combined with basic components gives a mixture of 1,2-pentanediol, 1,5-pentanediol and other by-products. The selectivity much depends on catalysts and reaction conditions, and good 1,2-pentanediol selectivity can be obtained. For 1,5-pentanediol synthesis, more selective approaches have been reported such as Cu-zeolite catalysts for furfuryl alcohol hydrogenolysis in flow reactor and M-M’Ox-type (M: noble metal; M’: transition metal) supported catalysts or Ni-LnOx (Ln: rare earth element) catalysts for tetrahydrofurfuryl alcohol hydrogenolysis. The metal catalysts and M-M’Ox-type catalysts can be applied to ring-opening hydrogenolysis of other furan- and tetrahydrofuran-based compounds, respectively. Among the products of ring-opening hydrogenolysis of biomass-derived compounds, 1,5-pentanediol seems to be the most important because of the potential use as a monomer. The recent progress and reported properties of polymers using 1,5-pentanediol as a monomer are also summarized.

This paper aimed to determine the susceptibility of polycarbonate and polymethylmethacrylate to corrosion cracking under specific operating conditions. The tests included static tensile and flexure, impact strength, and microscopic examination. Due to the synergistic effect of tensile stresses and seawater environment, numerous cracks are observed. Moreover, aging conditions did not significantly reduce the strength properties of the tested specimens; thus, higher resistance to stress corrosion cracking does not have a close relationship with the material's mechanical properties

La(III)‐catalyzed depolymerization of polycarbonates produces the raw carbonates and diols by transesterification without the use of bases, ionic liquids or additives. Poly(bisphenol A carbonate) (1 a) is depolymerized by [La(acac)3] (acac: acetylacetonate) (1 mol %) in MeOH at 135 °C for 20 min to give dimethyl carbonate (2 a) (95 %) and bisphenol A (3 a) (93 %). This reaction can also be carried out in the air using MeOH as received and on a 10 gram‐scale. A commercial compact disk (CD) can also be depolymerized quantitatively. Depolymerization of 1 a in EtOH or 1,2‐propanediol produces corresponding carbonate with 3 a. Poly(ethylene carbonate) (1 b) and poly(propylene carbonate) (1 c) are converted into dimethyl carbonate and corresponding glycols in high yields in MeOH. The kinetic study suggests the surface reaction mechanism for the La(III)‐catalyzed depolymerization of 1 a. [ABSTRACT FROM AUTHOR]

AbstractAmorphous polycarbonate (PC), amorphous polystyrene (PS), semicrystalline polyethylene oxide (PEO) and zinc sulfide (ZnS) nanoparticles (NP) were used to fabricate PC/PS/PEO/ZnS nanocomposite (NC) films. We believe that this study is novel in the area of the effect of γ ray radiation on such NC. The synthesized ZnS NP had an average particle size of 18 nm, as indicated from the Rietveld refinement of the X-ray diffraction (XRD) scans. Samples of the PC/PS/PEO/ZnS NC films were irradiated with γ ray doses ranging from 20 to 180 kGy. UV-vis spectroscopy and the International Commission on Illumination (CIE) color changes technique were used to investigate the resulting effects of the γ ray irradiation on the optical and color properties of the prepared films. The light absorbance of the NC films increased as it was irradiated with the γ ray doses up to 180 kGy, the maximum dose used. The increase in absorbance was associated with a decrease in the direct bandgap from 5.88 to 4.92 eV, and an increase of Urbach energy from 0.43 to 0.81 eV. This was attributed to the dominance of chain crosslinks. The γ ray effects on the absorbance, extinction coefficient, refractive index and optical conductivity of the NC films were studied. The modifications in the optical properties indicated that the γ radiation is a useful tool that allows the application of the resulting PC/PS/PEO/ZnS NC films in optoelectronic devices. Furthermore, the color differences between the pristine and irradiated films were evaluated using the CIE color differences technique. The pristine film was uncolored but showed significant color changes when irradiated with γ radiation up to 180 kGy, the maximum dose used. [ABSTRACT FROM AUTHOR]

Highlights Various sizing agents were prepared to enhance the interfacial properties between aramid fiber (AF) and polycarbonate (PC), as well as to enhance the mechanical properties of AF/PC composites. It was found that PC sizing agent, P‐GO sizing agent, and PSi‐GO sizing agent effectively coated the surface of AF from the FTIR and XPS and SEM results. The IFSS and mechanical properties of composites reinforced with fibers treated by the sizing agents exhibited significant improvement, as well as their single fiber tensile strength also improved. Specifically, when AF was treated with PSi‐GO sizing agent, the interfacial shear properties between AF and PC increased by a remarkable 78.69%, reaching 22.89 MPa compared to the original AF/PC composite, the tensile strength of the single‐filament exhibited an increment of 12.4% to 26.4 cN/dtex. Moreover, the tensile strength, flexural strength, and impact strength of the composite increased by 5.43%, 77.74%, and 54.71%, respectively. These improvement can be attributed to the GO with a higher concentration of chemical groups and excellent dispersion with modified with the silane agent. These findings suggest that coating the AF with sizing agents can effectively enhance its interfacial adhesion with the matrix, which is useful for its application as the reinforcement in the composites. Adding GO to the sizing agent to change the Aramid fabric surface properties. Silane coupling agent was used to improve the dispersion of GO on the fiber surface. GO modified sizing agent can improve the flexural strength, tensile strength, and interlaminar shear strength of the composites. [ABSTRACT FROM AUTHOR]

This study investigates the challenges and potential of conventional injection molding for producing thick-walled optical components. The research primarily focuses on optimizing process parameters and mold design to enhance product quality. The methods include software simulations and experimental validation using polycarbonate test samples (optical lenses). Significant parameters such as melt temperature, mold temperature, injection pressure, and packing pressure were varied to assess their impact on geometric accuracy and visual properties. The results show that lower melt temperatures and higher mold temperatures significantly reduce the occurrence of dimensional defects. Additionally, the design of the gate system was found to be crucial in minimizing defects and ensuring uniform material flow. Effective packing pressure was essential in reducing volumetric shrinkage and sink marks. Furthermore, we monitored the deviation between the predicted and actual defects relative to the thickness of the sample wall. After optimization, the occurrence of obvious defects was eliminated across all sample thicknesses (lenses), and the impact of the critical defect, the sink mark on the planar side of the lens, was minimized. These findings demonstrate the substantial potential of conventional injection molding to produce high-quality thick-walled parts when these parameters are precisely controlled. This study provides valuable insights for the efficient design and manufacturing of optical components, addressing the growing demand for high-performance thick-walled plastic products. [ABSTRACT FROM AUTHOR]

Incremental sheet forming has been largely investigated in the last two decades because of its versatility and cost-effectiveness, which make it viable for manufacturing highly customized parts as well as small- and medium-sized batches. This process allows for reaching greater formability compared to conventional sheet-forming processes. In contrast, it is affected by defects like twisting, which strongly influence the geometric accuracy of the formed parts. These aspects are dramatically accentuated when forming soft materials like thermoplastics. With these premises, the following research aims to investigate the effects of the toolpath strategy on the occurrence of failures and defects in the incremental sheet forming under very severe process conditions. Cone frusta with a fixed wall angle were obtained by thin polycarbonate sheets, imposing four unidirectional helical trajectory-based toolpaths, one traditional, and three stair strategies. The analysis of the forming forces, the evaluation of the worked surfaces, and the monitoring of the defectiveness highlight the advantages of a stair toolpath strategy in terms of reduced twisting and loading and high surface quality, regardless of the lubrication conditions. [ABSTRACT FROM AUTHOR]

Seeking high‐performance photoresists is an important item for semiconductor industry due to the continuous miniaturization and intelligentization of integrated circuits. Polymer resin containing carbonate group has many desirable properties, such as high transmittance, acid sensitivity and chemical formulation, thus serving as promising photoresist material. In this work, a series of aqueous developable CO2‐sourced polycarbonates (CO2‐PCs) were produced via alternating copolymerization of CO2 and epoxides bearing acid‐cleavable cyclic acetal groups in the presence of tetranuclear organoborane catalyst. The produced CO2‐PCs were investigated as chemical amplification resists in deep ultraviolet (DUV) lithography. Under the catalysis of photogenerated acid, the acetal (ketal) groups in CO2‐PC were hydrolysed into two equivalents of hydroxyl groups, which change the exposed area from hydrophobicity to hydrophilicity, thus enabling the exposed area to be developed with water. Through normalized remaining thickness analysis, the optimal CO2‐derived resist achieved a remarkable sensitivity of 1.9 mJ/cm2, a contrast of 7.9, a favorable resolution (750 nm, half pitch), and a good etch resistance (38 % higher than poly(tert‐butyl acrylate)). Such performances outperform commercial KrF and ArF chemical amplification resists (i.e. polyhydroxystyrene‐derived and polymethacrylate‐based resists), which endows broad application prospects in the field of DUV (KrF and ArF) and extreme ultraviolet (EUV) lithography for nanomanufacturing. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the bisphenol A (BPA) release from four CAD/CAM splint materials: three polycarbonate‐based (DD BioSplint C, Splint Plus Biostar, Temp Premium Flexible) and one polymethylmethacrylate‐based (Temp Basic) material. From each material, ten cylindrical samples (n = 40) were immersed in high‐performance liquid chromatography (HPLC) grade water following ISO 10993‐12 and incubated for 24 h in an incubation shaker at 37°C and 112 rpm. Following BPA derivatization, analysis was performed by high‐performance liquid chromatography–tandem mass spectrometry (HPLC‐MS/MS). After 24 h of incubation, all investigated materials released significant amounts of BPA compared to water blanks. The material‐dependent elution increased in the following order: DD BioSplint C < Splint Plus Biostar < Temp Basic < Temp Premium Flexible. Subtracting extraneous BPA, the concentrations ranged between 2.27 ng/mL and 12.65 ng/mL. After extrapolating the concentrations in relation to the average surface area of occlusal splints, the amount of BPA per mL exceeded the Tolerable Daily Intake (TDI) set by the European Union for a person weighing 70 kg by 1.32–6.16 times. Contrary to the release from previously investigated materials, BPA elution from CAD/CAM splint materials was highly elevated. Considering the increasing adaptation of CAD/CAM techniques, elution from them may represent a relevant BPA source in daily dental practice. [ABSTRACT FROM AUTHOR]

Visible light communication (VLC) is becoming more relevant due to the accelerated advancement of optical fibers. Polymer optical fiber (POF) technology appears to be a solution to the growing demand for improved transmission efficiency and high-speed data rates in the visible light range. However, the VLC system requires efficient splitters with low power losses to expand the optical energy capability and boost system performance. To solve this issue, we propose an effective 1 × 8 optical splitter based on multicore polycarbonate (PC) POF technology suitable for functioning in the green-light spectrum at a 530 nm wavelength. The new design is based on replacing 23 air-hole layers with PC layers over the fiber length, while each PC layer length is suitable for the light coupling of the operating wavelength, which allows us to set the right size of each PC layer between the closer PC cores. To achieve the best result, the key geometrical parameters were optimized through RSoft Photonics CAD suite software that utilized the beam propagation method (BPM) and analysis using MATLAB script codes for finding the tolerance ranges that can support device fabrication. The results show that after a light propagation of 2 mm, an equally green light at a 530 nm wavelength is divided into eight channels with very low power losses of 0.18 dB. Additionally, the splitter demonstrates a large bandwidth of 25 nm and stability with a tolerance range of ±8 nm around the operated wavelength, ensuring robust performance even under laser drift conditions. Furthermore, the splitter can function with 80% and above of the input signal power around the operated wavelength, indicating high efficiency. Therefore, the proposed device has a great potential to boost sensing detection applications, such as Raman spectroscopic and bioengineering applications, using the green light. [ABSTRACT FROM AUTHOR]

The effects of triethyl citrate (TEC) on the viscoelastic properties of a copolycarbonate comprising isosorbide and 1,4-cyclohexanedimethanol (ISB-PC) were studied in both the molten and solid states. TEC acted as an antiplasticizer for ISB-PC and increased its modulus in the glassy state, as demonstrated in blends comprising 5 and 10 wt% TEC. Because antiplasticization reduces the free volume fraction, the water content of the copolycarbonate films, which is known to affect various properties, decreased following the addition of TEC. Furthermore, TEC greatly decreased the zero-shear viscosity. The experimental values were much lower than those predicted by the Berry–Fox formula. In other words, a small amount of TEC greatly enhances the flowability of ISB-PC. [ABSTRACT FROM AUTHOR]

Luminescent polymer composites based on polycarbonate and polystyrene doped with boron difluoride β-ketoiminates have been synthesized. The luminescence properties of 12 dyes with various substituents have been studied. The effect of the boron difluoride β-ketoiminate concentration on the spectral properties of the samples has been studied. It has been found that the studied dyes exhibit monomer luminescence even with a tenfold increase in the luminophore concentration (from 0.05 to 0.5%). It has been revealed that composites containing boron difluoride 3-amino-1-phenyl-2-buten-1-onate (1a) and boron difluoride 3-methylamino-1-phenyl-2-buten-1-onate (2a) dyes in polystyrene exhibit exciplex luminescence. [ABSTRACT FROM AUTHOR]

Using styrene maleic anhydride copolymer (SMA) grafted onto silica nanoparticles, polycarbonate/acrylonitrile butadiene styrene copolymer (PC/ABS) blends were prepared by a two-step method, and the effect of SMA copolymer on the coefficient of thermal expansion (CTE) and impact strength of PC/ABS blends was investigated. The results showed that the addition of SMA copolymer resulted in a decrease in the flowability of PC/ABS blends, while their heat resistance was enhanced. Meanwhile, with the increase of SMA content, the CTE of PC/ABS blends decreased to varying degrees compared to S0, among which the CTE of S1, S2, S3 and S4 respectively decreased by 19.8%, 44.5%, 43.1%, and 41.4% compared to S0. The addition of SMA copolymer effectively improved the LOI value of PC/ABS composites, with S2 sample having the highest LOI value of 28.8%, and the UL-94 measurement result was V-0, with no dripping observed. In addition, with the increase of SMA copolymer content, the tensile strength of PC/ABS blends shows a trend of first increasing and then slightly decreasing, the bending strength shows a trend of first increasing and then stabilizing, the elongation at break shows a trend of first decreasing and then stabilizing, and the notch impact strength shows a continuous upward trend. Among them, the S2 sample has the highest tensile strength, bending strength, and high notch impact strength, with values of 41.6 MPa, 102.4 MPa, and 15.3 J/m², respectively, which are 29.6%, 10.7%, and 1.35 times higher than the corresponding parameters of the S0 sample. [ABSTRACT FROM AUTHOR]

Rechargeable polymer‐based solid‐state batteries with metallic lithium anodes and LiNixMnyCo1−x−yO2 (NMC)‐based cathodes promise safer high‐energy‐density storage solutions than existing lithium‐ion batteries, but have shown challenging to realize. The failure mechanisms that have been suggested for these battery cells have mostly been related to the use of a metallic lithium anode and formation of dendrites during cycling. Here, we approach the issue of using solid polymer electrolytes (SPEs) vs. NMC cathodes by employing a range of materials based on poly(ϵ‐caprolactone‐co‐trimethylene carbonate) (PCL‐PTMC) with different salts under various cycling conditions. It is seen that although the ionic conductivity of the electrolyte can be improved by exchanging the lithium salt, it does not immediately correlate to better cycling performance. However, increasing the temperature during battery cycling to improve the ion transport kinetics lowers the polarization of the battery cell and full capacity can be achieved at an upper voltage cut‐off that is appropriate for the polymer electrolyte. For these electrolytes, the limit is demonstrated to be 4.4 V vs. Li+/Li, and cycling with NMC‐111 cathodes is thereby possible provided that the upper cut‐off is limited to below this limit. [ABSTRACT FROM AUTHOR]

Improper end‐of‐life treatments of C−O‐linked plastics have caused serious environmental crises and resource waste. One effective method to solve this issue is the catalytic alcoholysis of these plastics. Traditional homogeneous catalysts or metal‐based heterogeneous catalysts for alcoholysis have some drawbacks, such as difficulty in complete separation, environmental threats, and economic burden. Thus, finding a green, low‐cost, recyclable, and highly efficient catalyst substitute is critical. Here, we reported that polymeric carbon nitride nanosheets can serve as a metal‐free heterogeneous catalyst for the methanolysis of polycarbonate, polyethylene terephthalate, and polylactic acid. The catalyst exhibits remarkable performance and could be reused at least four times. NHx was found to be the predominant active site of the catalyst by characterization and experiments. These results show promise for the design of metal‐free heterogeneous catalysts to depolymerize C−O‐linked plastics. [ABSTRACT FROM AUTHOR]

The results of the measurements of spall strength of polycarbonate at a maximum compression stress of 0.6 GPa in the initial temperature range of 20–185°C are presented. It has been found a significant decrease in the spall strength when the polycarbonate reached the glass transition temperature. The strain rates in the plastic compression wave are determined depending on the maximum stress under single and stepwise shock compression. The dependences of the shock wave velocity Us—mass velocity up in the range of maximum shock compression stresses up to 0.8 GPa at different temperatures are constructed. [ABSTRACT FROM AUTHOR]

The steep increase in carbon dioxide (CO2) emissions has created great concern due to its role in the greenhouse effect and global warming. One approach to mitigate CO2 levels involves its application in specific technologies. In this context, CO2 can be used for a more sustainable synthesis of polycarbonates (CO2-PCs). In this research, CO2-PC films and composites with multiwalled carbon nanotubes (MWCNTs, ranging from 0.2 to 7.0 wt.%) have been prepared to achieve more sustainable multifunctional sensing devices. The inclusion of the carbonaceous fillers allows for the electrical conductivity to be enhanced, reaching the percolation threshold (Pc) at 0.1 wt.% MWCNTs and a maximum electrical conductivity of 0.107 S·m−1 for the composite containing 1.5 wt.% MWCNTs. The composite containing 3.0 wt.% MWCNTs was also studied, showing a stable and linear response under temperature variations from 40 to 100 °C and from 30 to 45 °C, with a sensitivity of 1.3 × 10−4 °C−1. Thus, this investigation demonstrates the possibility of employing CO2-derived PC/MWCNT composites as thermoresistive sensing materials, allowing for the transition towards sustainable polymer-based electronics. [ABSTRACT FROM AUTHOR]

Graphite oxide (GO) was used to modify polycarbonate (PC) to prepare flame retardant PC composites and the effects of GO content on the flame retardancy, mechanical properties, and heat resistance of composites. The results showed that the flame retardancy and heat resistance of composites increased with the increase of GO content, and the tensile strength, bending strength, and impact strength of the composites continued to increase, while the elongation at break gradually decreased. When the GO content is 3%, the composites with good flame retardancy, mechanical properties, and heat resistance can be obtained. At this time, the limited oxygen index (LOI) of the composites reaches 32.8%, the flame retardancy level reaches V-0, and the total heat release (THR) and total smoke production(TSP) are reduced by 45.8% and 75.7%, respectively. Compared with pure PC, the tensile strength, bending strength, and impact strength are increased by 25.4%, 33.7%, and 63.2%, respectively, the elongation at break is reduced by 7.1%. The temperature at which the weight loss is 5% is increased by 19 °C, the peak temperature of thermal weight loss is increased by 52 °C, and the mass residual rate of thermal decomposition is increased by 8.9%. [ABSTRACT FROM AUTHOR]

AbstractNanocomposite films (NC) of amorphous polycarbonate (PC), semicrystalline polyethylene oxide (PEO), and chromium oxide (Cr2O3) nanoparticles (NP) were synthesized. We believe that this study is novel in the area of the effect of laser radiation on such NC. The synthesized Cr2O3 had a nanonature of average particle size 29 nm, as indicated from the Rietveld refinement of the XRD scans. Samples of the PC-PEO/Cr2O3 NC films were irradiated with infrared energy fluences ranging from 5 to 95 Joule/cm2 (J/cm2) using an infrared pulsed laser. We used UV-vis spectroscopy and the International Commission on Illumination (CIE) color changes technique to investigate the resulting effects of the laser irradiation on the optical bandgap energy and color properties of the prepared films. As the laser fluence increased up to 95 J/cm2, the maximum fluence used, both the direct and indirect bandgaps decreased. The Urbach energy showed an opposite tendency; it increased from 0.32 to 0.56 eV. This can be attributed to the dominance of chain crosslinks that destroyed the ordered structure and thus increased the amorphous regions. Also, the optical dielectric loss (ε″) aided in detecting the nature of the microelectronic transitions. It was found that the PC/PEO/Cr2O3 NC films had direct allowed transitions. Additionally, the effect of laser irradiation on the absorbance, refractive index, real and imaginary dielectric parameters, and optical conductivity of the blend composite samples were studied. Moreover, the optical color changes between the pristine and the irradiated films were evaluated. The pristine blend film was uncolored. It showed significant color changes when irradiated with the laser at increasing fluences up to 95 J/cm2. The change in the optical properties of PC/PEO/Cr2O3 NC film suggested its usage as a promising candidate for future optoelectronics manufacturing. [ABSTRACT FROM AUTHOR]

As one of the five major engineering plastics, polycarbonate (PC) has been applied in many industrial fields. However, its poor wear‐ and UV‐ resistance greatly limit its further promotion. Inspired by the dual benefits of inorganic–organic hybrid filler, in this study, we developed a novel type of catechol group‐ and nano silica‐containing reinforcing filler (CFNS) for the preparation of wear‐ and UV‐resistant PC‐based composite films. With a low level of filler content (1%), the coefficient of friction (COF) was distinctly reduced from 0.14 (neat PC film) to 0.06 (composite film), benefiting from a wear‐resistant surface layer. On the basis of ensuring high and stable transmittance for visible light, the composite films also exhibit strengthened capacity of UV shielding for the waveband from 293 to 400 nm. In addition, the general performance of composite films including tensile strength, tensile modulus, and thermal stability have also been improved in different degrees. Therefore, the composite films reinforced by CFNS are highly promising for a wide range of applications, ascribed to their improved general properties as well as two additional functions of wear‐ and UV‐resistance. [ABSTRACT FROM AUTHOR]