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Prevention of aseptic loosening, the main reason for secondary surgery of bone implants, is of great crucial clinical importance. As a promising bioactive material to promote bone regeneration, the piezoelectric materials for preventing aseptic loosening has not been reported. Here, a surface coating is presented for implants based on piezoelectric poly(L‐lactic acid) (PLLA). The coating ingeniously utilizes zoledronic acid (ZA), a drug used to treat osteoporosis, as a nucleating agent to enhance the piezoelectricity of PLLA. The coating can not only provide a continuous porous piezoelectric environment to stimulate osteogenic differentiation without intervention, but also effectively inhibit the osteolytic activity of osteoclasts through the slow release of ZA, achieving long‐term effectiveness with a single implantation. The rat femur cavity implantation experiment suggests that, the PLLA/ZA coating can rapidly initiate osseointegration of the implant and effectively mitigate the risk of aseptic loosening, even in the presence of metal submicroscopic particles that induce aseptic loosening. This strategy of piezo‐enhanced PLLA drug‐loaded coating may provide a new idea for the surface modification of bone implants. [ABSTRACT FROM AUTHOR]

The widespread application of polylactide (PLA) has been limited by its slow crystallization rate and poor toughness. In the present work, a low molecular weight nucleator, TMC 301, and polyamide elastomer (PAE) were incorporated into PLA through melt blending to mediate both the crystallization capability and impact toughness. It was found that the introduction of TMC 301 decreased the crystallization temperature of PLA during the cooling process, while enhancing its cold crystallization capacity of PLA in the heating scan. Accordingly, the presence of TMC 301 shortened the half-crystallization time of PLA at 95°C in the ternary blends with minimal influence on the Avrami index. Moreover, the dispersion size of PAE decreased when the concentration of TMC 301 increased to 0.3 wt%, leading to a substantial increase in the tensile toughness and the impact strength of the PLA/PAE/TMC 301 blend. It is suggested that the size of the elastomer particles is a critical factor influencing the toughening efficiency of TMC301 in PLA/PAE blends. The nucleator TMC 301 and polyamide elastomer (PAE) were incorporated into PLA through melt blending to enhance both crystallization capability and toughness. The phase structure, crystallization behavior and the mechanical performances were studied. [ABSTRACT FROM AUTHOR]

PLA was melt-blended with a chain extender (CEAX8840) and a nucleating agent (ST-NAB3) by using a torque rheometer, and the microstructure, crystallization behavior, mechanical properties, and heat resistance of the modified PLA were characterized by suing scanning electron microscope, hot-plate polarizing microscope, differential scanning calorimeter, thermal deformation meter, universal testing machine, and impact tester. The results indicated that the modified PLA obtained the smallest crystal size at CEAX8840 and ST-NAB3 contents of 6 and 1 wt%, respectively; however, its crystal density was the highest. Moreover, the crystallization temperature and crystallinity degree of the modified PLA were increased to 123. 9 °C and 44. 9 %, respectively. In addition, its impact strength and thermal deformation temperature were increased to 64. 7 kJ/m² and 84. 9 °C, respectively. [ABSTRACT FROM AUTHOR]

Abstract Biodegradable poly(L-lactide)-b-poly(ethylene glycol)-b-poly(L-lactide) (PLLA-PEG-PLLA) triblock copolymer could potentially be used in bioplastic applications because it is more flexible than PLLA. However, investigations into modifying PLLA-PEG-PLLA with effective fillers are still required. In this work, bamboo biochar (BC) was used as an eco-friendly and cost-effective filler for the flexible PLLA-PEG-PLLA. The influences of BC addition on crystallization properties, thermal stability, hydrophilicity, and mechanical properties of the PLLA-PEG-PLLA were explored and compared to those of the PLLA. The PLLA-PEG-PLLA matrix and BC filler were found to have strong interfacial adhesion and good phase compatibility, while the PLLA/BC composites displayed weak interfacial adhesion and poor phase compatibility. For the PLLA-PEG-PLLA, the addition of BC induced a nucleation effect that was characterized by a decrease in the cold crystallization temperature from 76 to 71–75 °C and an increase in the crystallinity from 18.6 to 21.8–24.0%; however, this effect was not observed for the PLLA. When compared to pure PLLA-PEG-PLLA, the PLLA-PEG-PLLA/BC composites displayed greater thermal stability, tensile stress, and Young’s modulus. Temperature at maximum decomposition rate (Td,max) of PLLA end-blocks increased from 315 to 319–342 °C. Ultimate tensile stress of PLLA-PEG-PLLA matrix improved from 14.5 to 16.2–22.6 MPa and Young’s modulus increased from 220 to 280–340 MPa. Based on the findings, the crystallizability, thermal stability, and mechanical properties of the flexible PLLA-PEG-PLLA bioplastic were all enhanced by the use of BC as a multi-functional filler.

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.)

Using benzoyl hydrazide and benzoyl chloride with different end-capping structures, three kinds of organic hydrazide nucleating agents, 1, 4-dibenzoyl p-phenylhydrazide (BTAD), 1, 4-bis(4-methylbenzoyl) p-phenylhydrazide (BTAD-CH3) and 1, 4-bis(4-tert-butylbenzoyl) p-phenylhydrazide [BTAD-(CH3)3], were prepared by coupling reaction. Their effects on crystallization behavior, mechanical properties and heat resistance of polyethylene terephthalate (PET) were also discussed. The results show that when the addition of nuclearing agents BTAD, BTAD-CH3 and BTAD-(CH3)3 are 1.0%, the crystallization peak temperature (Tc) of PET is increased by 51, 53, 56 °C, respectively, and the crystallinity (Xc) is increased from 18.1% to 26.3%, 26.9% and 29.7%, respectively. BTAD-(CH3)3 can further refine the size of PET spherulite and show better nucleation effect. When BTAD-(CH3)3 is added at 2.0%, the bending modulus of PET composites is increased to 2 675 MPa, with an increase of 22%, and the Vicat softening temperature and thermal deformation temperature are increased by 60 °C and 10 °C, respectively, compared with PET, and the mechanical properties and heat resistance are improved. [ABSTRACT FROM AUTHOR]

Globally, the demand for single-use plastics has increased due to the rising demand for food delivery and household goods. This has led to environmental challenges caused by indiscriminate dumping and disposal. To address this issue, non-degradable plastics are being replaced with biodegradable alternatives. Polylactic acid (PLA) is a type of biodegradable plastic that has excellent mechanical properties. However, its applications are limited due to its low crystallinity and brittleness. Studies have been conducted to combat these limitations using carbon or inorganic nucleating agents. In this study, waste cement and PLA were mixed to investigate the effect of the hybrid inorganic nucleating agent on the crystallinity and mechanical properties of PLA. Waste cement accelerated the lamellar growth of PLA and improved its crystallinity. The results indicate that the flexural and impact strengths increased by approximately 3.63% and 76.18%, respectively. [ABSTRACT FROM AUTHOR]

Poly(lactide acid) (PLA) foams have shown considerable promise as eco-friendly alternatives to nondegradable plastic foams, such as polystyrene (PS) foams. Nevertheless, PLA foam typically suffers from low heat-resistance and poor cellular structure stemming from its inherent slow crystallization rate and low melt strength. In this study, a high-performance PLA foam with well-defined cell morphology, exceptional strength and enhanced heat-resistance was successfully fabricated via a core-back microcellular injection molding (MIM) process. Differential scanning calorimetry (DSC) results revealed that the added hydrazine-based nucleating agent (HNA) significantly increased the crystallization temperature and accelerated the crystallization process of PLA. Remarkably, the addition of a 1.5 wt% of HNA led to a significant reduction in PLA's cell size, from 43.5 µm to 2.87 µm, and a remarkable increase in cell density, from 1.08×107 cells/cm3 to 2.15×1010 cells/cm3. This enhancement resulted in a final crystallinity of approximately 55.7% for the PLA blend foam, a marked improvement compared to the pure PLA foam. Furthermore, at 1.5 wt% HNA concentration, the tensile strength and tensile toughness of PLA blend foams demonstrated remarkable improvements of 136% and 463%, respectively. Additionally, the Vicat softening temperature of PLA blend foam increased significantly to 134.8 °C, whereas the pure PLA foam exhibited only about 59.7 °C. These findings underscore the potential for the preparation of lightweight injection-molded PLA foam with enhanced toughness and heat-resistance, which offers a viable approach for the production of high-performance PLA foams suitable for large-scale applications. [ABSTRACT FROM AUTHOR]

In this study, we prepared nanosponges (NS) by crosslinking the hydroxyl group of β-cyclodextrin (CD) molecular. Furthermore, we modified the CD molecular by 1, 2-cyclohexanediamine (TRK) through simple chemical method. CD, NS and CD-TRK were used as nucleating agent in the injection foaming process of polyethylene (PE) with 4, 4'-oxydibenzenesulfonyl hydrazide as blowing agent. With addition of CD-TRK, the crystallinity increased from 39.17% for pure PE to 46.02% for PE/CD-TRK-1.0 composites. Results showed that PE/CD-TRK-1.0 composites presented the best foam morphology. The cell density increased by about 10 times, while the cell diameter reduced by about 56% compared with that of pure PE. Scanning electron microscopy analysis showed that CD-TRK exhibited more compact and dense network structure with uniform cavity distribution, which may reduce the cell nucleation barrier and provide proper nucleation site for cells. The dynamic mechanical analysis showed that PE/CD-TRK-1.0 composites displayed proper modulus and viscoelasticity, which were favor for cell nucleation, growth and stabilization, resulting in the best cell morphology of PE/CD-TRK composites. Tensile and impact strength of foaming PE composites were systematically analyzed. The maximum impact strength reached 27.4 KJ·m−2, and the maximum tensile strength reached 27.5 MPa. [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.)

The type and structure of nucleating agents have an important influence on the properties of the final foam as well as on the nucleation of the bubbles during injection foaming. In this study, a simple melt blending method was used to prepare polypropylene/nucleating agents (PP/NAs) composites containing nucleating agents with different structures, and the rheological behavior of the PP/NAs composites was studied using a rotational rheometer. According to the rheological data, the structure of the nucleating agent was not the primary reason for influencing polymer viscosity. Additionally, PP/NAs composite foams were prepared by chemical foaming injection molding process and the bubble dynamics, cell quality and tensile properties were investigated. The results exhibited that polymers with β-cyclodextrin (β-CD), which had a self-contained cavity-circular table structure, as the nucleating agent have better bubble nucleation dynamics. The tensile toughness of PP/β-CD foam was increased from 8.21 MJ/cm3 to 20.54 MJ/cm3, an improvement of 150.34% by comparison with pure PP foam, which was attributed to having an average cell diameter of 23.98 μm and a cell density of 2.36 × 107 cells/cm3. Therefore, this study provides a reference for the design of efficient nucleating agents for the preparation of structural foam materials with lightweight and tough properties. [ABSTRACT FROM AUTHOR]

The sintered glass-ceramic always has an uneven microstructure due to the surface crystallization, which limits the enhancement of its mechanical properties. In the present work, Cr 2 O 3 was added into CaO–MgO–Al 2 O 3 –SiO 2 –CaCl 2 glass as the nucleating agent, and the low-pressure (14 kPa) sintering technology was utilized to promote the densification process of the glass frits (0.42–2 mm). It was found that by adding 1 wt% of Cr 2 O 3 , the bulk crystallization can be achieved inside the glass particle and the microstructure of the glass-ceramic became more homogeneous. Correspondingly, the bending strength was improved from 127 to 147 MPa, and the Vickers hardness was enhanced from 6.5 to 6.7 GPa, comparing with the Cr 2 O 3 -free glass-ceramic. The current study confirmed the positive impact of nucleating agent in the performance of sintered glass-ceramic, which also provided a route for the utilizations of CaCl 2 -and Cr 2 O 3 -bearing wastes. [ABSTRACT FROM AUTHOR]

An efficient and scalable method to prepare oligolactic acid stereocomplex microplates (SC‐OLA‐MPs) is developed. Oligolactic acid was firstly synthesized via the melt polycondensation of lactic acid. Then, the oligo (L‐lactic acid) and oligo (D‐lactic acid) were crystallized with a mixture of dichloromethane and acetone, and consequently the stereocomplex microparticles were obtained in the form of circular microplates with a diameter of approximately 2 μm. As an eco‐friendly nucleating agent, SC‐OLA‐MPs were introduced into poly (L‐lactic acid) (PLLA) via melt blending. The nonisothermal and isothermal crystallization of the SC‐OLA‐MPs/PLLA composites were investigated, and the crystal morphology and heterogeneous nucleation phenomena during the isothermal crystallization process were photographed with POM. SC‐OLA‐MPs show excellent nucleating effects on PLLA crystallization. With the incorporation of 10% SC‐OLA‐MPs, the crystallization half‐time of the SC‐OLA‐MPs/PLLA composite decreased from 7.18 to 0.45 min at 100°C, compared to the neat PLLA. Through a short‐time molding procedure, the thermal deformation temperature of PLLA is improved by the addition of SC‐OLA‐MPs. Highlights: Polylactic acid stereocomplex microplates were fabricated by solution crystallization.This method is easy and scalable.This microplate is an effective nucleating agent for PLLA. [ABSTRACT FROM AUTHOR]

The work evaluated the nucleating effect of nanometric zirconia (Zr-NP), obtained by the green sol-gel synthesis route using Euclea natalensis root extract as a reductant, in the low-density polyethylene (LDPE). The Zr-NP was characterized with x-ray diffraction (XRD) and transmission electron microscopy (TEM) which confirmed the presence of Zr-NP in the cubic crystalline phase with an average particle size of 6.73 nm. The Zr-NP was incorporated into the polymeric matrix by solubilization in concentrations ranging between 0 wt% and 6 wt%. Non-isothermal DSC analyzes demonstrated that a small addition of 1 wt% changes the degree of crystallinity from ~23% to ~56%, an increase of ~137%. The addition of Zr-NP also caused a small increase in crystallization and melting temperatures, and a large increase in the total crystallization time of LDPE.

Current research on materials engineering focuses mainly on bio-based materials. One of the most frequently studied materials in this group is polylactide (PLA), which is a polymer derived from starch. PLA does not have a negative impact on the natural environment and additionally, it possesses properties comparable to those of industrial polymers. The aim of the work was to investigate the potential of organosilicon compounds as modifiers of the mechanical and rheological properties of PLA, as well as to develop a new method for conducting mechanical property tests through innovative high-throughput technologies. Precise dosing methods were utilized to create PLA/silicone polymer blends with varying mass contents, allowing for continuous characterization of the produced blends. To automate bending tests and achieve comprehensive characterization of the blends, a self-created workstation setup has been used. The tensile properties of selected blend compositions were tested, and their ability to withstand dynamic loads was studied. The blends were characterized through various methods, including rheological (MFI), X-ray (XRD), spectroscopic (FTIR), and thermal properties analysis (TG, DSC, HDT), and they were evaluated using microscopic methods (MO, SEM) to examine their structures. [ABSTRACT FROM AUTHOR]

Sorbitol derivatives and other additives are commonly used in various products, such as packaging or food packaging, to improve their mechanical, physical, and optical properties. To accurately and precisely evaluate the efficacy of adding sorbitol-type nucleating agents to these articles, their quantitative determination is essential. This study systematically investigated the quantification of sorbitol-type nucleating agents in food packaging made from impact copolymers of polypropylene (PP) and polyethylene (PE) using attenuated total reflectance infrared spectroscopy (ATR-FTIR) together with analysis of principal components (PCA) and machine learning algorithms. The absorption spectra revealed characteristic bands corresponding to the C–O–C bond and hydroxyl groups attached to the cyclohexane ring of the molecular structure of sorbitol, providing crucial information for identifying and quantifying sorbitol derivatives. PCA analysis showed that with the selected FTIR spectrum range and only the first two components, 99.5% of the variance could be explained. The resulting score plot showed a clear pattern distinguishing different concentrations of the nucleating agent, affirming the predictability of concentrations based on an impact copolymer. The study then employed machine learning algorithms (NN, SVR) to establish prediction models, evaluating their quality using metrics such as RMSE, R2, and RMSECV. Hyperparameter optimization was performed, and SVR showed superior performance, achieving near-perfect predictions (R2 = 0.9999) with an RMSE of 0.100 for both calibration and prediction. The chosen SVR model features two hidden layers with 15 neurons each and uses the Adam algorithm, balanced precision, and computational efficiency. The innovative ATR-FTIR coupled SVR model presented a novel and rapid approach to accurately quantify sorbitol-type nucleating agents in polymer production processes for polymer research and in the analysis of nucleating agent derivatives. The analytical performance of this method surpassed traditional methods (PCR, NN). [ABSTRACT FROM AUTHOR]

The EFSA Panel on Food Contact Materials, Enzymes and Processing Aids assessed the safety of calcium tert‐butylphosphonate, which is intended to be used as a nucleating agent up to 0.15% w/w for the manufacture of polyolefin food contact materials (FCM) and articles for single and repeated use, in contact with all types of food, including infant formula and human milk. Specific migration was tested using polyethylene samples in 10% ethanol, 3% acetic acid and 95% ethanol for 2 h at 100°C, followed by 238 h at 40°C. Results for all three simulants were near or below the limit of detection of 10 μg/kg. As the solubility of the substance is far above the reported migration and above 60 mg/kg food, no assessment of the particle fraction was needed, and the conventional risk assessment was followed. The substance did not induce gene mutations in bacterial cells and structural chromosomal aberrations in mammalian cells, thus, did not raise concern for genotoxicity. The Panel considered that the use of the substance did not give rise to safety concern related to neurotoxicity for the general population, but this conclusion could not be applied to infants below 16 weeks of age, due to their specific sensitivity and the absence of dedicated data. The Panel concluded that calcium tert‐butylphosphonate does not raise a safety concern for the consumer if it is used as a nucleating agent up to 0.15% w/w in the manufacture of polyolefin FCM that are intended to be in contact with all types of food for storage above 6 months at room temperature and below, including temperatures up to 100°C for maximum 2 h and up to 130°C for short durations. The Panel could not evaluate the safety of use to manufacture FCM for contact with infant formula and human milk. [ABSTRACT FROM AUTHOR]

Poly(L-lactide)-b-poly(ethylene glycol)-b-poly(L-lactide) (PLLA-PEG-PLLA) shows promise for use in bioplastic applications due to its greater flexibility over PLLA. However, further research is needed to improve PLLA-PEG-PLLA's properties with appropriate fillers. This study employed zinc phenylphosphate (PPZn) as a multi-functional filler for PLLA-PEG-PLLA. The effects of PPZn addition on PLLA-PEG-PLLA characteristics, such as crystallization and thermal and mechanical properties, were investigated. There was good phase compatibility between the PPZn and PLLA-PEG-PLLA. The addition of PPZn improved PLLA-PEG-PLLA's crystallization properties, as evidenced by the disappearance of the cold crystallization temperature, an increase in the crystallinity, an increase in the crystallization temperature, and a decrease in the crystallization half-time. The PLLA-PEG-PLLA's thermal stability and heat resistance were enhanced by the addition of PPZn. The PPZn addition also enhanced the mechanical properties of the PLLA-PEG-PLLA, as demonstrated by the rise in ultimate tensile stress and Young's modulus. We can conclude that the PPZn has potential for use as a multi-functional filler for the PLLA-PEG-PLLA composite due to its nucleating-enhancing, thermal-stabilizing, and reinforcing ability. [ABSTRACT FROM AUTHOR]

Boron-mullites are potential candidate crystal phases for broadband near-infrared (NIR) luminescence in the mullite series due to their higher complexity in crystal structure and abundant [AlO 6 ] units for accommodating transition metal ions as luminescence activators. In this work, the effect of ZrO 2 and TiO 2 on the microstructure and NIR luminescent properties of mullite type Cr3+:Al 4 B 2 O 9 glass ceramics were analyzed in detail. Through characterizations including XRD, SEM, TEM and NMR, the oriented growth of strip-shaped grains in ZrO 2 doped glass ceramic samples has been verified. The proportion of [AlO 6 ] units is strongly correlated with NIR spectra, suggesting that the strategy for modulation the NIR luminescence through oriented growth can be generalized as a universal method for manipulation of the optical properties for transition metal ion activated crystals with the mullite type structure. [ABSTRACT FROM AUTHOR]

Short‐life packaging has been contributing to the increased consumption of polymers. Expanded polystyrene (EPS) is a material that is widely used in disposable packaging, however, its residue occupies a large volume, is difficult to degrade, and its recycling is expensive. That's why the interest in looking for a material of natural and biodegradable origin that can be an alternative to petrochemical‐based polymers. One possibility would be starch, which is a natural and biodegradable polysaccharide and can be extracted from different sources. However, natural starch does not have good properties for commercial application, requiring chemical modifications and/or the incorporation of additives. This article carried out a compilation of current studies that work on the development of packaging, whether film or foams, based on plasticized starch (TPS), and analyzes the influence of the incorporation of additives or treatments carried out in the starch. The blowing agent decreases foam density, cell size, and increases cell density. Incorporation of glycerol in starch foams increases the gelatinization temperature, decreases viscosity and resistance to expansion. The surfactant decreases the density and moisture absorption of the foam, the nucleating agent acted by increasing the mechanical strength and density of the foam, and decreases the absorption of water. [ABSTRACT FROM AUTHOR]

A linear diamides derivative (TMC-300) was incorporated into biosourced and biodegradable poly(3-hydroxybutyrate-co-4-hydroxybutyrate) (P34HB) to investigate the influence of TMC-300 on the crystallization and rheological properties of P34HB. TMC-300 displayed an outstanding nucleating effect on P34HB. Adding 0.5 mass% TMC-300 increased the non-isothermal crystallization temperature by about 20 °C at rate of 5 °C min−1. Isothermal crystallization half-time at 95 °C obviously decreased from 20 min for neat P34HB to 2.5 min for P34HB/0.2TMC. Adding TMC-300 dramatically increased nucleation density and reduced spherulite size. Moreover, the rheological properties were obviously enhanced by adding TMC-300. The most intriguing result was that percolation network was formed at TMC-300 content between 0.5 and 1 mass%, which led to the transition of melt behaviors from liquid-like to solid-like. The unusual combination of nucleating effect and rheological properties promotion of TMC-300 on P34HB was in great potential for expanding practical application of biosourced and biodegradable P34HB. [ABSTRACT FROM AUTHOR]

The main purpose of this work is to present the effect of long-chain branching and specific α-nucleation on the optical properties, crystallization and supermolecular structure of polypropylene (PP). Commercially available α-nucleating/clarifying agent 1,3;2,4-bis(3,4-dimethylbenzylidene)sorbitol (Millad 3988) was mixed into linear PP and long-chain branched PP (LCB-PP) in the concentration of 0.2 wt%. For the study of polymorphic composition, crystallinity, and crystallization process under isothermal conditions in the temperature range of 130–150 °C, differential scanning calorimetry and wide-angle X-ray scattering were used. Although the used nucleating/clarifying agent appears to have a slight effect on the optical properties of long-chain branched polypropylene, it does not appear to affect the crystallization kinetics significantly. LCB-PP exhibited self-nucleation, favored over nucleation by a specific nucleating agent.

As semi-crystalline polyester (lactic acid) (PLA) is combined with other reinforcing materials, challenges such as phase separation, environmental pollution, and manufacturing difficulties could hinder the benefits of PLA, including complete biodegradability and strong mechanical properties. In the present investigation, melt blending is utilized to establish a mixture of low- and high-molecular-weight polylactic acids (LPLA and HPLA). The crystallinity, rheology, and mechanical properties of the combination were analyzed using rotational rheometry, differential scanning calorimetry, X-ray diffraction, polarized optical microscopy, scanning electron microscopy, and universal testing equipment. The results demonstrate compatibility between LPLA and HPLA. Moreover, an increase in LPLA concentration leads to a decrease in the crystallization rate, spherulite size, fractional crystallinity, and XRD peak intensity during isothermal crystallization. LPLA acts as a diluent during isothermal crystallization, whereas HPLA functions as a nucleating agent in the non-isothermal crystallization process, promoting the growth of LPLA crystals and leading to co-crystallization. The blended system with a 5% LPLA mass fraction exhibits the highest tensile strength and enhances rheological characteristics. By effectively leveraging the relationship between various molecular weights of PLA's mechanical, rheological, and crystallization behavior, this scrutiny improves the physical and mechanical characteristics of the material, opening up new opportunities. [ABSTRACT FROM AUTHOR]

In this study, the influence of a super absorbent polymer (SAP) addition on the thermal properties of phase change material (PCM) was investigated. It was found that adding SAP reduced the melting temperature of PCM and improved phase separation properties. While the addition of 1.0 wt% of SAP to PCMs decreased latent heat by 3 J/g to 24.4 J/g, the addition was determined to be necessary to prevent leaks from a functional duct unit (FDU) and assure product stability. The results obtained from a series of brine refrigeration tests indicate that the supercooling temperature decreased by 0.3 °C to 1.7 °C when 1.0 wt% of SAP was added to PCM. The addition of SAP to PCM appears to promote supercooling by encouraging condensation during phase change. As a result of applying SAP-added PCM to the FDU, the isothermal operation performance was improved compared to existing refrigerators. [ABSTRACT FROM AUTHOR]

In this work, a novel α-nucleating agent (NA) for polypropylene (PP) termed APAl-3C-12Li was prepared and evaluated compared with the commercially available type NA-21. For the synthesis of the organophosphate-type NA (APAl-3C), the -OH group of the acid part of NA-21 was substituted by the isopropoxy group. The structure of APAl-3C was analyzed by spectroscopy and element analysis, the results of which were consistent with the theoretical molecular formula. APAl-3C's thermal stability was studied by differential scanning calorimetry (DSC) and thermogravimetry (TG), which showed only weak mass loss below 230 °C, meaning that it would not decompose during the processing of PP. The APAl-3C-12Li was used as a novel nucleating agent, studying its effects on crystallization, microstructure, mechanical and optical properties. Tests were performed in a PP random copolymer at different contents, in comparison to the commercial NA-21. The composite with 0.5 wt% APAl-3C-12Li has a similar crystallization temperature of 118.8 °C as with the addition of 0.5 wt% NA-21. An advantage is that the composite with the APAl-3C-12Li has a lower haze value of 9.3% than the counterpart with NA-21. This is due to the weaker polarity of APAl-3C-12Li after the introduction of methyl and better uniform dispersion in the PP matrix, resulting in stronger improvement of optical and mechanical properties. [ABSTRACT FROM AUTHOR]

The purpose of this study is to investigate the use of nucleating agent to improve the overall performance of polybutylene adipate-co-terephthalate (PBAT) and calcium carbonate (CaCO3) composites. Specifically, sodium linoleate (Na-LL) is used as a chemical nucleating agent to improve the crystallization behavior of the material during melting extrusion processing. Mechanical, thermal, and morphological characteristics of PBAT and its composites were investigated. And a preliminary exploration was conducted on the mechanism of Na-LL improving the performance of PBAT. In this work, a formula has been obtained that dramatically saves production costs while improving product performance. After adding Na-LL to the composites, the thermal properties of the material were significantly improved, with a maximum crystallization temperature increase of 27.79 °C. In addition, composites offer superior mechanical properties compared to pure PBAT. When 0.2 parts by mass(pbw) Na-LL was added, the flexural modulus of the composites increased from 80.0 to 145.3 MPa, increased by 81.25%. The tensile performance can still be maintained at 11.0 Mpa, with elongation at break and impact strength reduced to 347.3% and 172.1 J/m, respectively. Under these conditions, it has excellent comprehensive mechanical properties. The results in this study suggest that Na-LL is a promising nucleating agent for enhancing the performance of composites and provides potential development of advanced materials for a wide range of applications in plastic packaging and plastic bags. [ABSTRACT FROM AUTHOR]

The development of high-performance and low-cost composite nucleating agents has become a pioneering point in expanding the application of isotactic polypropylene (iPP). To this end, this article used a physical blending method to mix nucleating agent organic phosphate salt (LPN-9081) with inorganic fillers such as wollastonite and talc powder. Change the ratio of nucleated mineral-reinforced composition LPN-9081/wollastonite (L/WO) and LPN-9081/talc powder (L/Tac) to study their effects on the crystallization, melting behavior, and mechanical properties of iPP. And a preliminary exploration was conducted on its mechanism. The results suggest that the nucleated mineral-reinforced composition more significantly enhance the crystallization temperature, increasing it by up to 10 °C. Furthermore, it was observed that the mechanical properties of iPP were significantly improved via the synergistic effect of LPN-9081 and the inorganic fillers. In the iPP/L/WO system, the addition of the composite nucleating agent improved rigidity by 146% while maintaining toughness. Similarly, compared with iPP system, the iPP/L/Tac system has improved its rigidity by 107% and toughness by 50%. Using the nucleated mineral-reinforced compositions mentioned above can reduce industrial expenses, while increases the rigidity and toughness of iPP, expanding its potential of applications. [ABSTRACT FROM AUTHOR]

A notable application of polymeric nanocomposites is the design of water vapor permeable (WVP) membranes. "Breathable" membranes can be created by the incorporation of micro/nanofillers, such as CaCO3, that interrupt the continuity of the polymeric phase and when subjected to additional uniaxial or biaxial stretching this process leads to the formation of micro/nanoporous structures. Among the candidate nanofillers, carbon nanotubes (CNTs) have demonstrated excellent intrinsic WVP properties. In this study, chemically modified MWCNTs with oligo olefin-type groups (MWCNT-g-PP) are incorporated by melt processes into a PP matrix; a β-nucleating agent (β-ΝA) is also added. The crystallization behavior of the nanocomposite films is evaluated by differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The WVP performance of the films is assessed via the "wet" cup method. The nanohybrid systems, incorporating both MWCNT-g-PP and β-NA, exhibit enhanced WVP compared to films containing only MWCNT-g-PP or β-NA. This improvement can be attributed to the significant increase in the growth of α-type crystals taking place at the edges of the CNTs. This increased crystal growth exerts a form of stress on the metastable β-phase, thereby expanding the initial microporosity. In parallel, the coexistence of the inherently water vapor-permeable CNTs, further enhances the water vapor permeability reaching a specific water vapor transmission rate (Sp.WVTR) of 5500 μm.g/m2.day in the hybrid composite compared to 1000 μm.g/m2.day in neat PP. Notably, the functionalized MWCNT-g-PP used as nanofiller in the preparation of the "breathable" PP films demonstrated no noteworthy cytotoxicity levels within the low concentration range used, an important factor in terms of sustainability. [ABSTRACT FROM AUTHOR]

The use of nucleating agents (NAs) to accelerate semicrystalline polymers crystallization is a widely recognized technique during processing. However, the commercially available NA for poly(phenylene sulfide) (PPS) has been rather limited. In this work, it is found that calcium pimelate (CaPim), a commercial nucleating agent for isotactic polypropylene, could also accelerate the crystallization process of PPS. The influence of CaPim addition on the crystallization behaviors of PPS was investigated under non‐isothermal and isothermal condition. Upon the addition of 0.3 wt% CaPim, the crystallization peak temperature and the onset crystallization temperature increases by 5.3 and 8.4°C at 10°C/min cooling rate, and the half‐time of crystallization reduces 51% at crystallization temperature of 272°C. Polarized optical observation revealed a substantial enhancement in nucleation due to the presence of CaPim. Avrami equation analysis suggested that the nucleating agent significantly increased the crystallization rate constant without affecting the growth dimension. Moreover, Lauritzen–Hoffman theory analysis indicateed that the addition of CaPim lowers the nucleation energy barrier, contributing to its high‐nucleation efficiency. These findings demonstrate that calcium pimelate holds promise as an effective nucleating agent for PPS. [ABSTRACT FROM AUTHOR]

The main purpose of this work is to present the effect of long-chain branching and specific α-nucleation on the optical properties, crystallization and supermolecular structure of polypropylene (PP). Commercially available α-nucleating/ clarifying agent 1,3;2,4-bis(3,4-dimethylbenzylidene)sorbitol (Millad 3988) was mixed into linear PP and long-chain branched PP (LCB-PP) in the concentration of 0.2 wt%. For the study of polymorphic composition, crystallinity, and crystallization process under isothermal conditions in the temperature range of 130-150 °C, differential scanning calorimetry and wide-angle X-ray scattering were used. Although the used nucleating/clarifying agent appears to have a slight effect on the optical properties of long-chain branched polypropylene, it does not appear to affect the crystallization kinetics significantly. LCB-PP exhibited self-nucleation, favored over nucleation by a specific nucleating agent. [ABSTRACT FROM AUTHOR]

Abstract The EFSA Panel on Food Contact Materials, Enzymes and Processing Aids assessed the safety of calcium tert‐butylphosphonate, which is intended to be used as a nucleating agent up to 0.15% w/w for the manufacture of polyolefin food contact materials (FCM) and articles for single and repeated use, in contact with all types of food, including infant formula and human milk. Specific migration was tested using polyethylene samples in 10% ethanol, 3% acetic acid and 95% ethanol for 2 h at 100°C, followed by 238 h at 40°C. Results for all three simulants were near or below the limit of detection of 10 μg/kg. As the solubility of the substance is far above the reported migration and above 60 mg/kg food, no assessment of the particle fraction was needed, and the conventional risk assessment was followed. The substance did not induce gene mutations in bacterial cells and structural chromosomal aberrations in mammalian cells, thus, did not raise concern for genotoxicity. The Panel considered that the use of the substance did not give rise to safety concern related to neurotoxicity for the general population, but this conclusion could not be applied to infants below 16 weeks of age, due to their specific sensitivity and the absence of dedicated data. The Panel concluded that calcium tert‐butylphosphonate does not raise a safety concern for the consumer if it is used as a nucleating agent up to 0.15% w/w in the manufacture of polyolefin FCM that are intended to be in contact with all types of food for storage above 6 months at room temperature and below, including temperatures up to 100°C for maximum 2 h and up to 130°C for short durations. The Panel could not evaluate the safety of use to manufacture FCM for contact with infant formula and human milk.

Globally, the demand for single-use plastics has increased due to the rising demand for food delivery and household goods. This has led to environmental challenges caused by indiscriminate dumping and disposal. To address this issue, non-degradable plastics are being replaced with biodegradable alternatives. Polylactic acid (PLA) is a type of biodegradable plastic that has excellent mechanical properties. However, its applications are limited due to its low crystallinity and brittleness. Studies have been conducted to combat these limitations using carbon or inorganic nucleating agents. In this study, waste cement and PLA were mixed to investigate the effect of the hybrid inorganic nucleating agent on the crystallinity and mechanical properties of PLA. Waste cement accelerated the lamellar growth of PLA and improved its crystallinity. The results indicate that the flexural and impact strengths increased by approximately 3.63% and 76.18%, respectively.

In this study, graphene quantum dots (GQDs) with a diameter of ~3 nm were successfully synthesized and incorporated into a poly(ethylene terephthalate) (PET) matrix to fabricate PET/GQDs nanocomposites. The impact of GQDs on the crystallization and thermal stability of the PET/GQDs nanocomposites was investigated. It was observed that the addition of only 0.5 wt% GQDs into the nanocomposites resulted in a significant increase in the crystallization temperature (peak temperature) of PET, from 194.3 °C to 206.0 °C during the cooling scan process. This suggested that an optimal concentration of GQDs could function as a nucleating agent and effectively enhance the crystallization temperature of PET. The isothermal crystallization method was employed to analyze the crystallization kinetics of the PET/GQDs nanocomposites, and the data showed that 0.5 wt% GQDs significantly accelerated the crystallization rate. Furthermore, the incorporation of GQDs into the PET matrix imparted photoluminescent properties to the resulting PET/GQDs nanocomposites. The PET crystals with GQDs as crystal nuclei and the crazes caused by defects played a vital role in isolating and suppressing the concentration quenching of GQDs. This effect facilitated the detection of defects in PET. [ABSTRACT FROM AUTHOR]

Lightweight plastic foam materials can save resources and energy and reduce environmental pollution. However, these plastic components with large cell sizes present unsatisfactory mechanical properties. Here, we describe a successful strategy to fabricate lightweight and tough polypropylene/nucleating agent (PP/NA) composite foams with high cell density and small cell size by combining designed nanoparticles with intrinsic cavities as nucleating agents and chemical foam injection molding technologies. The influences of nucleating agents with different contents, morphologies, and process parameters on the cell morphology of pure PP and PP/NA foam samples were studied systematically. Owning to the effective increase of the number of nucleation sites by introducing SiO2 nanoparticles with pits on the surface (NAC), the lightweight and tough PP/NAC composite foam that the addition amount of NAC of 1 wt % (PPC1) was prepared with a high cell density of 1.22 × 107 cells/cm3 and a small cell size of 27.99 μm, which enhanced the tensile strength from 21.47 to 24.31 MPa and caused a 356.06% increase in tensile toughness. Furthermore, the effects of packing time on the foaming behavior of PPC1 were studied. When packing time is 5 s, the average cell size is 17.01 μm and the cell density reaches 3.01 × 107 cells/cm3, enhancing the tensile strength to 25.36 MPa and causing a 557.52% increase in the tensile toughness. Therefore, this work provided insights into fabrication of lightweight and tough PP/NA composite foams, which have great promise as structure materials for future use in many applications, such as automotive. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA) is a biodegradable polyester, but its low crystallization rate and excessive embrittlement limit its application. Decanedioic acid 1,10‐bis (2‐benzoylhydrazide) (TMC‐300) as an effective nucleating agent of PLA will induce PLA epitaxial crystallization and improve the crystallization rate of PLA. This article studied the promoting behavior of TMC‐300 with different contents in composite systems on PLA crystallization. The results showed that with the increase of TMC‐300 content, the crystallinity can be significantly increased, up to 22 times, and t1/2 significantly decreases. Meanwhile, with the addition of TMC‐300, the typical spherical crystal morphology of PLA gradually became attached to TMC‐300 fibrous crystal morphology. In terms of mechanical properties, the tensile strength reached its maximum at 0.5 wt% of TMC‐300 content, increasing from 60.60 MPa (PLA) to 74.59 MPa (0.5‐TMC‐300), an increase of 23.09%. At this time, due to the reduction in spherical crystal size, the elongation at break also increased significantly. However, the thermal stability of PLA composites deteriorated with the increase of nucleating agent content due to the low thermal decomposition temperature of TMC‐300 itself, and the Tmax decreased from 372°C (PLA) to 353°C (5‐TMC‐300), a decrease of 19°C. [ABSTRACT FROM AUTHOR]

High-molecular-weight poly(L-lactide) (HMW-PLLA), which is a biocompatible, biodegradable, and bio-based polymer, is an alternative to traditional petroleum-based plastics. However, its poor crystallizing ability limits its widespread application. In this paper, low-molecular-weight poly(L-lactic acid) (LMW-PLLA) and poly(D-lactic acid) (LMW-PDLA) synthesized through polycondensation of L-lactic acid and D-lactic acid, respectively, were used to prepare stereocomplex poly(lactic acid) (scPLA) powder using precipitation technique. Nucleation efficiency of the obtained scPLA powder was investigated by melt blending with the HMW-PLLA. The scPLA powder was nearly spherical in shape, had a single melting peak at 205 °C and exhibited complete stereocomplex crystallites. According to the differential scanning calorimetry (DSC) and X-ray diffractometry (XRD) analyses, the added scPLA powder improved the crystallization of HMW-PLLA and increased the crystallinity content of HMW-PLLA. Scanning electron microscopy (SEM) showed good phase compatibility between dispersed scPLA particles and HMW-PLLA matrices. The addition of scPLA powder had no significant effect on the tensile properties of the HMW-PLLA matrix. In conclusion, scPLA powder prepared from blending of polycondensation LMW-PLLA and LMW-PDLA showed a promising behavior to enhance the crystallized ability of HMW-PLLA. [ABSTRACT FROM AUTHOR]

In order to study the influence of the peripheral substituent position of sorbitol acetal molecule on its nucleation effect, three sorbitol acetal nucleating agents which are isomers of each other were synthesized. The crystallization process of polypropylene (PP) before and after modification was analyzed, and the effects of sorbitol acetal nucleating agent on the morphology, structure and properties of PP was studied. The results show that the three sorbitol acetal nucleating agents are α crystalline nucleating agents, among which the para-substituted sorbitol acetalization nucleating agent has the best performance, and has the best improvement effects on the optical properties and mechanical properties of PP. The haze is reduced from 78% to 16%, and the crystal grains are the most uniform and dense, and the crystallization temperature is the highest. The para-substituted sorbitol acetal nucleating agent is an efficient α crystalline transparent nucleating agent for PP. [ABSTRACT FROM AUTHOR]

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Sorbitol derivatives and other additives are commonly used in various products, such as packaging or food packaging, to improve their mechanical, physical, and optical properties. To accurately and precisely evaluate the efficacy of adding sorbitol-type nucleating agents to these articles, their quantitative determination is essential. This study systematically investigated the quantification of sorbitol-type nucleating agents in food packaging made from impact copolymers of polypropylene (PP) and polyethylene (PE) using attenuated total reflectance infrared spectroscopy (ATR-FTIR) together with analysis of principal components (PCA) and machine learning algorithms. The absorption spectra revealed characteristic bands corresponding to the C–O–C bond and hydroxyl groups attached to the cyclohexane ring of the molecular structure of sorbitol, providing crucial information for identifying and quantifying sorbitol derivatives. PCA analysis showed that with the selected FTIR spectrum range and only the first two components, 99.5% of the variance could be explained. The resulting score plot showed a clear pattern distinguishing different concentrations of the nucleating agent, affirming the predictability of concentrations based on an impact copolymer. The study then employed machine learning algorithms (NN, SVR) to establish prediction models, evaluating their quality using metrics such as RMSE, R2, and RMSECV. Hyperparameter optimization was performed, and SVR showed superior performance, achieving near-perfect predictions (R2 = 0.9999) with an RMSE of 0.100 for both calibration and prediction. The chosen SVR model features two hidden layers with 15 neurons each and uses the Adam algorithm, balanced precision, and computational efficiency. The innovative ATR-FTIR coupled SVR model presented a novel and rapid approach to accurately quantify sorbitol-type nucleating agents in polymer production processes for polymer research and in the analysis of nucleating agent derivatives. The analytical performance of this method surpassed traditional methods (PCR, NN).

Current research on materials engineering focuses mainly on bio-based materials. One of the most frequently studied materials in this group is polylactide (PLA), which is a polymer derived from starch. PLA does not have a negative impact on the natural environment and additionally, it possesses properties comparable to those of industrial polymers. The aim of the work was to investigate the potential of organosilicon compounds as modifiers of the mechanical and rheological properties of PLA, as well as to develop a new method for conducting mechanical property tests through innovative high-throughput technologies. Precise dosing methods were utilized to create PLA/silicone polymer blends with varying mass contents, allowing for continuous characterization of the produced blends. To automate bending tests and achieve comprehensive characterization of the blends, a self-created workstation setup has been used. The tensile properties of selected blend compositions were tested, and their ability to withstand dynamic loads was studied. The blends were characterized through various methods, including rheological (MFI), X-ray (XRD), spectroscopic (FTIR), and thermal properties analysis (TG, DSC, HDT), and they were evaluated using microscopic methods (MO, SEM) to examine their structures.

Poly(L-lactide)-b-poly(ethylene glycol)-b-poly(L-lactide) (PLLA-PEG-PLLA) shows promise for use in bioplastic applications due to its greater flexibility over PLLA. However, further research is needed to improve PLLA-PEG-PLLA’s properties with appropriate fillers. This study employed zinc phenylphosphate (PPZn) as a multi-functional filler for PLLA-PEG-PLLA. The effects of PPZn addition on PLLA-PEG-PLLA characteristics, such as crystallization and thermal and mechanical properties, were investigated. There was good phase compatibility between the PPZn and PLLA-PEG-PLLA. The addition of PPZn improved PLLA-PEG-PLLA’s crystallization properties, as evidenced by the disappearance of the cold crystallization temperature, an increase in the crystallinity, an increase in the crystallization temperature, and a decrease in the crystallization half-time. The PLLA-PEG-PLLA’s thermal stability and heat resistance were enhanced by the addition of PPZn. The PPZn addition also enhanced the mechanical properties of the PLLA-PEG-PLLA, as demonstrated by the rise in ultimate tensile stress and Young’s modulus. We can conclude that the PPZn has potential for use as a multi-functional filler for the PLLA-PEG-PLLA composite due to its nucleating-enhancing, thermal-stabilizing, and reinforcing ability.

A series of polyacrylic salts are used as nucleating agents in isotactic polypropylene (iPP). Investigations are done on the mechanical characteristics, crystallization behavior, and melting behavior of nucleated iPP. According to the result from differential scanning calorimetry (DSC), the temperature at which nucleated iPP crystallize was 3–5 °C higher than the temperature at which pure iPP. Meanwhile, zinc polyacrylate, potassium polyacrylate, and sodium polyacrylate have the ability to induce β-crystals in iPP, according to wide-angle X-ray diffraction data. The optical microscope observation combined with DSC results shows that potassium polyacrylate had a β-nucleation effect when it had a lamellar crystal structure. When compared to pure iPP, the impact strength of iPP nucleated with sodium polyacrylate or potassium polyacrylate is improved by 23.48% and 24.35%, respectively. According to the mechanical properties results, there is no significant change in the tensile strength and flexural modulus of nucleated iPP with sodium polyacrylate and potassium polyacrylate. Without compromising its stiffness, sodium polyacrylate or potassium polyacrylate can increase the toughness of nucleated iPP. [ABSTRACT FROM AUTHOR]

The foaming of PP has encountered challenges because of its low melt strength and semi-crystalline characteristics. Introducing long chain branching (LCB) onto the PP backbone and the addition of particles as cell nucleating agent are the commonly used methods to improve the cell structure of PP foams. In this paper, clay-supported sodium benzoate (NaB-OMMT) was prepared from Na-montmorillonite (Na-MMT) via the partial ion exchange reaction with surfactant and subsequent reaction with benzoic acid. The as prepared NaB-OMMTs were then applied to prepare LCBPP/NaB-OMMT nanocomposites and their foams. The dispersion state of clay, crystallization behaviors and rheological properties of the nanocomposites, as well as the cell structure and compression properties of the foams were investigated. The results show that clay layers are mostly exfoliated in the nanocomposites with low NaB-OMMT content, while intercalated layers dominant with the content reaches 2% or higher. The melting temperature of the nanocomposites decreases and the crystallinity increases, while the spherulite size decreases compared to LCBPP. The melt viscosity and elasticity of nanocomposites increase significantly when the content of NaB-OMMT reaches 2% or higher. LCBPP/NaB-OMMT nanocomposites foams exhibit higher cell density, smaller cell size and its standard deviation. Therein, the foam with 1% of NaB-OMMT shows the maximum cell density and the minimum cell size. It is concluded that the cell structure of the foam is highly dependent on the content, dispersion state and structure of the cell nucleating agent. When NaB is supported on well dispersed and exfoliated clay layers, the cell nucleation efficiency is significantly enhanced. The compression properties of the foams depend on their cell structures and exhibit the similar variation trend with the latter with the content of NaB-OMMT increasing. Graphical Abstract [ABSTRACT FROM AUTHOR]

This review paper analyzes the development of advanced class polylactide (PLA) materials through a combination of stereocomplexation and nanocomposites approaches. The similarities in these approaches provide the opportunity to generate an advanced stereocomplex PLA nanocomposite (stereo-nano PLA) material with various beneficial properties. As a potential "green" polymer with tunable characteristics (e.g., modifiable molecular structure and organic–inorganic miscibility), stereo-nano PLA could be used for various advanced applications. The molecular structure modification of PLA homopolymers and nanoparticles in stereo-nano PLA materials enables us to encounter stereocomplexation and nanocomposites constraints. The hydrogen bonding of D- and L-lactide fragments aids in the formation of stereococomplex crystallites, while the hetero-nucleation capabilities of nanofillers result in a synergism that improves the physical, thermal, and mechanical properties of materials, including stereocomplex memory (melt stability) and nanoparticle dispersion. The special properties of selected nanoparticles also allow the production of stereo-nano PLA materials with distinctive characteristics, such as electrical conductivity, anti-inflammatory, and anti-bacterial properties. The D- and L-lactide chains in PLA copolymers provide self-assembly capabilities to form stable nanocarrier micelles for encapsulating nanoparticles. This development of advanced stereo-nano PLA with biodegradability, biocompatibility, and tunability properties shows potential for use in wider and advanced applications as a high-performance material, in engineering field, electronic, medical device, biomedical, diagnosis, and therapeutic applications. [ABSTRACT FROM AUTHOR]

In this study, recycled high-density polyethylene (REHDPE)/black shale (B-shale) composites were prepared by a melt-blending method using a B-shale nucleating agent and polyolefin elastomer (POE) and acrylic impact modifier (ACR) as plasticizers. The melt index, microstructure, mechanical properties, and non-isothermal crystallization behavior of REHDPE were analyzed to determine the effects of the nucleating agent and plasticizer. Scanning electron microscopy and the melt index indicated that POE and ACR increased the melt flow rate of the composites and improved the interfacial properties of B-shale and REHDPE. The non-isothermal crystallization processes of the REHDPE and REHDPE composites were successfully described by Hoffmann–Lauritzen theory, demonstrating that B-shale, POE, and ACR can synergistically accelerate the crystallization process of REHDPE. The Friedman method revealed that B-shale, POE and ACR reduced the crystallization activation energy by heterogeneous nucleation and increasing the melt flow, respectively. The POE and ACR further enhanced the nucleation activity of B-shale and the nucleation activity is negatively correlated with the B-shale content according to the Dobreva and Gutzow's methods. The synergistic effect of nucleating agent and plasticizer improved the mechanical properties of REHDPE and solved the problem in relatively low mechanical properties of recycled plastics. And it will provide a new strategy for the practical production of REHDPE. [ABSTRACT FROM AUTHOR]