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In order to mimic hierarchical nanostructures in nature, particles of polymer blends consisting of poly(4-butyltriphenylamine) (PBTPA), poly(methyl methacrylate) (PMMA) and PBTPA-block-PMMA were fabricated by a solvent evaporation method. Effects of the molecular weight and the chemical composition of PBTPA-b-PMMA, molecular weights of homopolymers, and the composition of the blend on the morphology were investigated. The polymer blend particle consisting of PBTPA and PMMA homopolymers exhibited thermodynamically favored core-shell structure, in which more hydrophilic PMMA-shell surrounded PBTPA-core. The addition of 10 wt% of PBTPA-b-PMMA caused the morphological transition from core-shell to Janus or inversed core-shell, in which PBTPA-shell surrounded PMMA-core, depending on the molecular weight of PBTPA segment in PBTPA-b-PMMA. When the molecular weight of PMMA segment was higher than that of PMMA homopolymer, watermelon-like particles in which small PBTPA domain less than 80 nm dispersed in the PMMA domain surrounded by PBTPA shell were observed. As the ratio of PBTPA-b-PMMA increased, the interface of the macrophase separation became obscure. At 50 wt% of the PBTPA-b-PMMA, only microphase separation was observed. The measurement of interfacial tension by pendant drop method demonstrated that PBTPA-b-PMMA lower the interfacial tension between PBTPA and the aqueous phase to the value similar to that of PMMA with the aqueous phase.

The article presents an application of curcumin, a widely available and cost-effective organic dye, to control visible-light mediated ATRP. A two-component photocatalytic system composed of curcumin and an amine-based electron donor activates alkyl bromide and controls radical polymerizations by a reductive quenching pathway. The polymerizations of various types of (meth)acrylates were performed under blue LED irradiation (λmax = 460 nm, 5 mW cm−2). The effect of electron donor type, solvent, photocatalyst and electron donor concentration, target degree of polymerization (DPtarget) etc. on the metal-free ATRP of methyl methacrylate (MMA) and poly(ethylene glycol) methyl ether methacrylate (OEGMA500) was systematically investigated to optimize the polymerization conditions. Moreover, comestible curcumin of four different brands available in the market as kitchen spices was used, which makes this approach economical (∼0.04 € for 15 g of turmeric). In order to increase the applicability of the curcumin-based polymerization strategy, the concept was extended to the polymerization of other methacrylates – butyl methacrylate (nBMA), di(ethylene glycol) methyl ether methacrylate (DEGMA), 2-(dimethylamino)ethyl methacrylate (DMAEMA), and acrylates i.e. poly(ethylene glycol) methyl ether acrylate (OEGA480), n-butyl acrylate (nBA) and 2-hydoxyethyl acrylate (HEA). In situ chain extension experiment demonstrated the preservation of chain-end functionality, enabling the facile synthesis of well-controlled copolymers.

In this work, a new type of solid amine sorbent was developed for low concentration CO2 capture at ambient temperature. Polyacrylonitrile(PAN)-poly(methyl methacrylate)(PMMA) porous hollow fibers were firstly prepared by a wet-spinning process. Tetraethylenepentamine(TEPA) was then grafted onto the porous structure of the hollow fibers. The amine modified hollow fibers denoted as TEPA@PAN-PMMA were characterized by the Fourier transform infrared spectroscopy (FT-IR), thermo-gravimetric analysis(TGA), Brunauer-Emmett-Teller(BET), and scanning electron microscopy(SEM) methods. Performance of the TEPA@PAN-PMMA for CO2 capture was evaluated by passing a 0.3% CO2-N2 gas mixture through the porous matrix of the hollow fibers at ambient temperature. The highest CO2 adsorption capacity reached up to 1.50 mmol g−1 for dry feed, and 3.00 mmol g−1 for wet feed, respectively. Cyclic CO2 adsorption-desorption test indicated that the TEPA@PAN-PMMA sorbents are stable and regenerable.

We investigated the influence of barium titanate NPs on the optical characteristics of a (polystyrene-poly methyl methacrylate) blend. The solution casting technique is used to prepare (PS-PMMA) polymer blend and (PS-PMMA-BaTiO3) nanocomposites. The results indicate that as barium titanate concentrations increase, the absorbance of nanocomposites increases. The optical characteristics of (PS-PMMA-BaTiO3) nanocomposites (Coefficient of absorption, Coefficient of extinction, Index of refraction, Dielectric constant's real and imaginary components) increase as barium titanate NPs concentration increases. Gap of the energy narrows as the concentration of barium titanate nanoparticles increases.

Poly(methyl methacrylate) (PMMA) has received significant attention in recent years and is regarded as one of the most efficient and promising polymer with applications in diverse fields. This review discusses the applications of PMMA and PMMA-based materials in the field of dentistry. The use of PMMA as bone cement, denture base resin, filler, and base material has been described in detail. Also, the use of poly(methyl methacrylate) for temporary dental restorations, including implants or long-span bridges, was studied. Specifically, this review aims to explain the applications of poly(methyl methacrylate) in dentistry.

In this research study, poly(methyl methacrylate) (PMMA) polymer was selected and irradiated with alpha particles at various times. The alterations in the structure, optical parameters, and electrical properties of PMMA polymer caused by alpha particles have been assessed using XRD, ultraviolet–visible (UV/Vis) spectrophotometry and dc electric circuit, respectively. The results showed halo peaks in the XRD patterns, which indicate the amorphous nature of this type of polymer. The UV/Vis spectra demonstrated that absorption increases while transmittance decreases with an increase in the exposure time. Use of PMMA polymer as alpha dosimeters using the UV/Vis spectroscopic technique was investigated. The optical energy-gap values decreased from 3.44 eV to 3.01 eV. Furthermore, the refractive index values of all studied samples increased. Increasing the alpha radiation time enhanced dc-conductivity as well.

Background: The denture-base acrylic resins used by partially edentulous patients can cause local demineralization of teeth. Alkali ions released from the bioactive materials that were added to acrylic resins can increase the pH of the oral environment and slow down the demineralization process. Aim of the study: This study aimed to create a new denture-base acrylic resin that can release ions. Materials and methods: A total of 222 samples with different fillers (calcium hydrogen phosphate, hydroxyapatite, two kinds of bioactive glasses, and a product obtained by reaction between bioactive glass formed from glass ionomer cement and polyacrylic acid) were prepared for the study. All the materials were tested for mechanical properties and their use as phosphate donors for 3 weeks. The measurements were presented as mean ± SD error of the mean. Data were analyzed by two-way analysis of variance, with a p-value of

Understanding drug miscibility in pharmaceutically relevant systems is essential for the development and optimisation of pharmaceutical dosage forms. This is particularly true for film forming systems which are designed to become supersaturated with drug, following application on the skin surface, whilst maintaining the physical stability of the drug for a suitable period to enhance drug delivery. For such formulations, chemical penetration enhancers as well as the drug are absorbed from the formulation into the skin, making understanding drug delivery from the films challenging. This study investigated the use of an optical differential scanning calorimetry (DSC) to understand drug miscibility in polymeric film forming systems and explain drug transport behaviour from film forming formulations, containing ibuprofen, a copolymer based on dimethylaminoethyl methacrylate, butyl methacrylate, and methyl methacrylate (Eudragit® E, EuE), a copolymer based on ethyl acrylate, methyl methacrylate and methacrylic acid ester with quaternary ammonium groups (Eudragit® RS, EuRS) and a copolymer based on methacrylic acid and methyl methacrylate (Eudragit® S, EuS), with and without the chemical penetration enhancer propylene glycol, across a model membrane. The optical DSC enabled the rapid screening of not only drug-polymer miscibility, but also drug-vehicle miscibility, while considering both the melting-point depression and melting enthalpy of the drug due to the presence of the polymer/polymer-based vehicle, obtained via thermal analysis by structural characterisation (TASC) and DSC analysis, respectively. The results obtained enable the polymers studied to be ranked in the order of EuE > EuRS > EuS, with EuE being more miscible with ibuprofen, and the incorporation of a penetration enhancer in the film forming system formulation was found to increase ibuprofen solubility in EuE- and EuRS- based films. The drug-polymer/vehicle miscibility information obtained via optical DSC provided understanding of drug transport from film forming systems with the higher miscibility of ibuprofen with EuE reducing drug transport through decreasing drug saturation in the film. The higher drug transport from films containing EuRS and EuS could also be linked to drug miscibility with the polymer and showed dependence on ibuprofen loading in the formulation. Overall optical DSC has been demonstrated to be a valuable tool for determining drug-vehicle miscibility for pharmaceutical product development.

Hypothesis Micro/nanopatterning on a 2D surface is apt for cutting-edge miniaturization technology, which directly or indirectly requires high-end expensive lithographic tools. The evaporative deposition at the receding contact-line of a polymer solution, termed as Dynamic Contact Line Lithography (DCLL), can be a potential inexpensive technique for template-less meso-patterning if the deposition patterns from DCLL can be predicted a priori. Experiments A deposition map (morphological phase diagram) from the myriads of patterns is constructed in terms of contact-line velocity and the polymer concentration. Specifically, two combinations: polystyrene (PS)/cyclohexane and poly (methyl methacrylate) (PMMA)/toluene are used to show the generic nature of the phase diagrams. The surface wettability of Si (water contact angle, CA ~15°) is tuned from CA ~35° to ~98° by patterning with DCLL. Findings Directed by the phase diagrams, fabrication of a complex rectangular cross-pattern of PS and PMMA micro-threads with a periodicity of ~65 μm and ~50 μm respectively on a Si surface is demonstrated to establish the robustness and potential of the DCLL and predictive phase diagram.

The incompatibility between wood components and polymers negatively affects the physical and mechanical properties of wood polymer composites, which is still an obstacle to fabricating wood polymer composites with desirable performance. Inspired by the good compatibilization of Janus structure, silica Janus nanosheets were synthesized by sol–gel process and used to improve the interfacial interaction of methyl methacrylate (MMA)-impregnated wood in the present study. Results showed that the Janus nanosheets with smooth convex surfaces and rough concave surfaces were successfully synthesized. The thickness of Janus nanosheets was about 30 nm, and the length could be tuned by the time of the ultrasonication. With the addition of 0.5% nanosheets, the interface gaps between the polymer and wood cell wall were remarkably decreased compared to the MMA treated wood samples, indicating the efficient interfacial interaction due to Janus nanosheets. This improved interfacial interaction was also confirmed by the changes of the pore structure of MMA/Janus nanosheets-treated wood samples. The ASE of MMA/Janus sheets-treated wood was improved by 40% compared to MMA-treated wood samples. Compared to untreated wood samples, the water uptake of MMA/Janus sheets-treated wood was reduced by 61%, while the modulus of rupture and modulus of elasticity were improved by 31% and 45%, respectively, which were higher than MMA-treated wood. Moreover, the incorporation of silica nanosheets also improve the thermal stability of the MMA treated wood sample. This preliminary research will provide a new approach for enhancing the interfacial properties of wood polymer composites.

Self-crosslinking soap-free latexes (PMS) were synthesized by semi-continuous polymerization from methyl methacrylate and styrene with N-(hydroxymethyl)acrylamide (NAM) as high-temperature self-crosslinker and 2-acrylamido-2-methyl-1-propanesulfonic acid as reactive emulsifier. All PMS latexes with varying NAM contents (0–7 wt%) processed high solid contents (~30%) and monodispersed nano-micro particle sizes (180–600 nm). With augment of NAM content, monomer conversion slightly decreased while particle size decreased and then gradually increased, accompanied with increase of coagulum content. The self-crosslinking behavior showed highly dependence on NAM content and temperature, and the self-crosslinked structures were confirmed by FT-IR, XPS, DSC and SEM. The self-crosslinking latexes effectively improved rheological and microporous filtration properties of bentonite-based drilling fluid. Owing to stronger interparticle interactions, the latexes exhibited better viscosity-increasing effect after thermal treatment and stronger fluid-loss-reducing ability at high temperature. The microporous plugging mechanism was revealed to be the combination of heat deforming and self-crosslinking film forming besides physical bridging and filling.

Copolymers of poly(pentyl acrylate-co-methyl methacrylate) [P(PA-co-MMA)] were manufactured by using carbon dioxide with dispersion polymerization. The thermophysical characteristics of P(PA-co-MMA) were researched with three kinds ratios (1:20, 1:25, and 1:30) of PA vs. MMA and AIBN concentrations of (1.0, 2.0, and 4.0) wt%. Experimental product source at pressures of p ≤ 206 MPa and temperature of T ≤ 434 K was investigated for two- and three-components solution of P(PA-co-MMA) under compressed CO2, CHClF2, CHF3 and CH2F2. Experiments are carried out to get phase separation measurement for the two-component solution of P(PA-co-MMA) [1:25 mole ratio, AIBN of (1.0, 2.0 and 4.0 wt%] + compressed fluorine solvents (CHF3, CHClF2and CH2F2) solutions at a pressure of p

Copolymers of poly(methyl methacrylate)-co-poly (2-acrylamido-2-methyl-1-propane sulfonic acid (PMMA-co-PAMPS) have been prepared via radical polymerization with different MMA to AMPS mol ratio and blended with polyvinylidene fluoride (PVDF) and sulfonated PVDF (S-PVDF) in a different weight ratio to prepare proton exchange membranes (PEMs) by simple solution casting method for fuel cells application (PEMFCs). Five different PEMs have been prepared from only PMMA-co-PAMPS, blending PMMA-co-PAMPS with PVDF, and also by blending PMMA-co-PAMPS with S-PVDF to get the suitable membrane for PEMFCs application. We have also studied the effect of PVDF and S-PVDF in the blend membranes on the water uptake, mechanical stability, thermal stability, proton conductivity (Km), and methanol permeability ( P M ) properties. PEMs prepared by blending with S-PVDF exhibited high Km and low P M value. PEM-5 membrane prepared by blending S-PVDF with PMMA-co-PAMPS (30:70 w/w) exhibited Km at room temperature 5.7 × 10−2 S/cm, PM value 5.24 × 10−7 cm2/s and maximum power density 477 mW/cm2. This P M value is much lower than that of the Nafion® 117 membrane (22 × 10−7 cm2/s). This low P M , high Km and high selectivity make the S-PVDF blend membranes a good candidate in PEMFCs or direct methanol fuel cells (DMFCs) application.

This research is focused on the experiment of molecular imprinting polymers by supercritical solvent technology as friendly-environmental process. Methyl methacrylate (MMA) monomer, methacrylic acid (MAA) monomer, VA (vanillic acid) with template and EGDMA (ethylene glycol dimethacrylate) with cross-linking agent were used for molecular imprinting polymers composition. The template has been eliminated by the Soxhlet extraction method, and the rate of elimination is ca. 95–98 %. The adsorption capacities of the synthesized molecular imprinting polymers were estimated using the kinetics and isotherms of restraint, Scatchard investigation, affinity distributions, the materials adsorption with template-like structure, α (selectivity parameter), and HPLC (high performance liquid chromatography) analysis. The evaluation result shows that the manufactured molecular imprinting polymers have highly selectivity and separation ability. It was also confirmed that there was a difference between the adsorption amounts with EGDMA contents. In this study, prepared molecular imprinting polymers had an advantage in adsorption selectivity where VA and its structural analog materials are present. These results show that the molecular imprinting polymers selectivity was increased using control the cross-linking agent.

Magnetic starch microspheres (AAM-MSM) were synthesized via an inverse emulsion graft copolymerization by using mechanically activated cassava starch (MS) as a crude material, acrylic acid (AA) and acrylamide (AM) as graft copolymer monomers, and methyl methacrylate (MMA) as the dispersing agent and used as an adsorbent for the removal of Cd(II) ions from aqueous solution. Fourier-transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and vibrating sample magnetometry (VSM) were used to characterize the AAM-MSM adsorbent. The results indicated that AA, AM, and MMA were grafted to the MS, and the Fe3O4 nanoparticles were encapsulated in the AAM-MSM adsorbent microspheres. The adsorbent exhibited a smooth surface, uniform size, and good sphericity because of the addition of the MMA and provided more adsorption sites for the Cd(II) ions. The maximum adsorption capacity of Cd(II) on the AAM-MSM was 39.98 mg·g−1. The adsorbents were superparamagnetic, and the saturation magnetization was 16.7 A·m2·kg−1. Additionally, the adsorption isotherms and kinetics of the adsorption process were further investigated. The process of Cd(II) ions adsorbed onto the AAM-MSM could be described more favorably by the pseudo-second-order kinetic and Langmuir isothermal adsorption models, which suggested that the chemical reaction process dominated the adsorption process for the Cd(II) and chemisorption was the rate-controlling step during the Cd(II) removal process.

Poly (methyl methacrylate) (PMMA) bone cement is widely used as a filler for repairing bone defects. To improve the effectiveness of the treatment for bone defects caused by metastatic bone tumours, we propose the formulation of PMMA cement containing titania (TiO2) and magnetite (Fe3O4) that offers high bone affinity, making the cement suitable for use in magnetic hyperthermia. The TiO2 and Fe3O4 contents of the PMMA cement varied from 20 to 45 mass%. The various cement samples were evaluated for their apatite-forming ability and heat-generation characteristics. The samples containing TiO2 in concentrations of 15 mass% or higher formed apatite on their surfaces within 14 days in a simulated body fluid. The heat-generation characteristics of the samples were evaluated by applying an alternating current (AC) magnetic field under the following conditions: |H| = 40 Oe and f = 600 kHz, or |H| = 100 Oe and f = 100 kHz. The surface temperatures of the samples containing 25 and 30 mass% Fe3O4 reached 42.3 and 44.8 °C, respectively, at |H| = 40 Oe and f = 600 kHz. During hyperthermia treatment, cancer cells die at temperatures higher than 42 °C, and the cement samples fabricated in this study could reach this temperature. However, since some degree of heat loss will occur in vivo, it is necessary to ensure that the temperature is higher than 42 °C by varying the AC magnetic field. Nevertheless, the fact that the samples containing Fe3O4 concentrations of 25 mass% or higher generated enough heat under the AC magnetic field makes them suitable for clinical use in hyperthermia. Thus, PMMA cement containing 15 mass% or more of TiO2 and 25 mass% or more of Fe3O4 should be investigated as a bioactive bone cement with a strong hyperthermia effect.

This study demonstrates a novel type of biphasic calcium phosphate (BCP) gyroid scaffolds featuring of gyroid macroporous structure and micropous BCP walls using poly(methyl methacrylate) (PMMA) microspheres as the porogen for ceramic digital light processing (DLP) technique. To tailor the microporosity of the BCP walls and the overall porosity of the dual-scale porous BCP scaffolds, the PMMA content with regard to the BCP powder was controlled in the range of 40 vol% to 70 vol%. After debinding at 600 °C and sintering at 1200 °C for 3 h, micropores were uniformly created throughout each BCP framework, while preserving 3−dimensional gyroid macroporous structures. As the PMMA content increased from 40 vol% to 70 vol%, the microporosity remarkably increased from 31.9 (±2.5) vol% to 55.2 (±1.4) vol%. This approach allowed the achievement of very high overall porosities (82.2–89.7 vol%) for the dual-scale porous scaffolds. However, all the scaffolds showed reasonable compressive strengths (0.8 MPa −2.1 MPa), which are comparable to those of cancellous bones.

Blends of polyacrylonitrile (PAN) with three different sacrificial polymers: poly (acrylic acid) (PAA), poly (methyl methacrylate) (PMMA), and poly (styrene-co-acrylonitrile) (SAN), were gel spun, oriented through the drawing process, stabilized and carbonized to obtain porous carbon fibers. Carbon fibers with an average pore diameter of 15 nm, 31 nm, 37 nm and 115 nm have been obtained from PAN-PAA (90/10), PAN-PMMA (90/10), PAN-SAN (90/10) and PAN-SAN (80/20) precursor fibers, respectively. The variation in pore size caused by the differences in compatibility between PAN and the sacrificial polymer was evaluated experimentally through blend rheology and theoretically using interaction parameter values. Despite their porosity, carbon fibers from PAN-PAA (90/10) and PAN-PMMA (90/10) exhibited tensile strength (∼1.6 GPa) comparable to that of the non-porous PAN based carbon fibers, processed under similar conditions. Specific tensile modulus of the porous carbon fibers was 15–40% higher than that for the PAN based carbon fibers, and the electrical conductivity was as high as 74 kS/m due to high graphitic ordering. Porous channels presented in this study were obtained by combining phase separation in the nano/micro scale range, with pore orientation and elongation achieved through gel spinning.

The protein corona on nano drug carriers is an important well-known biological issue that often induce biological incompatibility and screens the targeting molecules on the surfaces of carriers, therefore, the design of NPs with good protein corona-free property is highly desired and challenged. The natural polysaccharide has been demonstrated as one types of stealth materials after the functional group modification process, but the types and structures of their chains has never been considered. Here, we have designed five types of core-shell starch-coated poly (methyl methacrylate) nanoparticles and we found the starch coated NPs with low amylose content (

The most common method chosen by artists, designers, and craftsmen to realize artworks and objects with transparent poly(methyl methacrylate) (PMMA) is to bond pieces from premanufactured sheets using solvents or adhesives. This method is considered relatively easy to use, however achieving bonds that are both transparent and strong can be difficult. Artifacts from museum collections made by bonding transparent PMMA often exhibit a variety of bonding defects and failures not yet addressed in depth in the conservation literature. Therefore, an international project started with the aims of classifying these bonding issues and understand their causes. This paper presents the results of the first part of this project which included the following research activities: surveys of bonding defects in PMMA artworks and design objects in museum collections, a literature review of the most recommended materials and methods used to bond PMMA over time, the preparation of bonded PMMA mock-ups based on literature review, chemical characterization of the bonding materials, thermal ageing of mock-ups, and finally technical examinations of the PMMA bonded mock-ups. The main defects observed in the museum objects surveyed were successfully recreated in the lab and the causes of their formation were assessed.

Size exclusion chromatography is the method of choice for the molar mass analysis of polymers, however, it is not selective towards polymer microstructure. Counterintuitively, asymmetric flow field-flow fractionation (AF4), a channel-based molar mass analysis technique, has been shown to be able to fractionate poly(methyl methacrylate (PMMA) according to tacticity. This was revealed by investigating the solution behaviour of syndiotactic- (s-PMMA), atactic- (a-PMMA) and isotactic (i-PMMA) poly(methyl methacrylate) of similar molecular masses in solvents with different thermodynamic properties. In addition to developing a selective fractionation method, the effects of solvent quality and channel temperature on the fractionation were investigated. It was concluded that the thermodynamic quality of the carrier liquid has a significant influence on the retention behaviour of polymers in AF4. It was shown that the separation of s-PMMA and i-PMMA can be improved by using a theta solvent (acetonitrile) as the carrier liquid instead of thermodynamically good solvents such as tetrahydrofuran and chloroform. In addition, it was found that by using a non-stereocomplexing solvent for PMMA, such as chloroform, blends of s-PMMA and i-PMMA can be separated. Lastly, it was established that the AF4 channel temperature has an influence on the retention behaviour of the PMMA samples. For THF as carrier liquid it was found that the maximum difference in retention between s-PMMA and i-PMMA can be achieved at a channel temperature of 35 °C. In the case of ACN being the carrier liquid, it was observed that the retention behaviour of i-PMMA was significantly more influenced by a change in temperature as compared to s-PMMA and a-PMMA.

The present work studied the synthesis of biolubricants from by-products of soybean oil processing using the lipase from Candida rugosa (CRL) both in free and immobilized forms, as biocatalysts. Soybean fatty acid distillate (SFAD) was used for first time as source of free fatty acids (FFA) to produce biolubricants via their enzymatic esterification with neopentyl glycol (NPG) and trimethylolpropane (TMP) alcohols in a solvent-free medium. The immobilization of CRL was performed via interfacial activation using a commercial hydrophobic support (Accurel) and a home-made core-shell matrix of poly(methyl methacrylate) (PMMA). Conversions of about 80 % were obtained using lyophilized CRL after 30 or 180 min using NPG and TMP, respectively. When CRL-PMMA/PMMA was used to catalyze the synthesis of NPG esters, 90 % conversion was achieved after only 6 h, whilst CRL-Accurel were more active using TMP. The biocatalysts maintained the reaction conversion during eight batches of 24 h. The lubricant properties of the products were also characterized, showing that it can be an environmentally friendly alternative for petrol lubricants

In the present paper, the laminar burning velocity and structure of near-stoichiometric premixed laminar flames of methyl methacrylate (MMA) with and without trimethylphosphate (TMP) additives have been studied experimentally and by numerical modeling. The MMA+TMP combustion system is considered as a model system, which simulates gas-phase combustion of polymethyl methacrylate (PMMA) with additive of phosphorus-containing fire retardants (PFRs). The motivation of the present research is to provide a basis for development of a predictive gas-phase chemical kinetic model for inhibition of PMMA by PFRs. The flame sampling molecular beam mass spectrometry was used to determine the spatial variation of the mole fractions of H, OH, PO, PO2, HOPO, HOPO2 and some intermediate hydrocarbons in the one-dimensional burner-stabilized flames. The effect of TMP on the hydrocarbon intermediates in the flames is investigated. The reaction mechanism for combustion of MMA+TMP system has been validated against the novel laminar burning velocity and chemical speciation data. Performances and deficiencies of the kinetic mechanism for MMA flame inhibition are discussed. The sensitivity analysis showed that the insufficiently accurate prediction of mole fraction of H, O and OH results in disagreement for mole fraction profiles of hydrocarbon intermediates in the inhibited flame. Inhibition effectiveness of MMA flame by TMP is compared with that derived from experimental data for other fuels and the observed tendencies are discussed.

Organic luminescent nanofibers owing to their flexibility and anisotropic emission along the axis when compared to direction perpendicular to axis are gaining much importance as luminescent probes and in a variety of other optic applications. Of the different organic luminescent nanofibers the one which is of recent interest is the rare earth integrated electrospun polymeric nanofibers. Among different host matrices the most suitable one is polymer in view of electrospinning technique as it facilitates the spinnability of the solution which is a matter of concern when coming to electrospinning technique and also enhances the flexibility of the product. Rare earths are the most apt material of choice when the research focus into luminescent applications. Among a number of rare earths of choice the one with greater potential is undoubtedly europium ion because of its intense emission in the orange red region on UV excitation. In the present study the polymer chosen is poly (styrene-co-methyl methacrylate) which is a copolymer of polystyrene and polymethyl methacrylate and the rare earth integrated is LaPO4:Eu3+. The surface morphologyanalysis and optical characterizations are done by SEM, EDX, XRD, PL and IR techniques. The sem analysis shows that the average fiber diameter distribution increased from the range of 70 nm to 120 nm on integration of LaPO4:Eu3+. The shift of maximum excitation wavelength in the UV spectra and presence of characteristic bands of Eu3+ ions in the region 579 to 610 nm in the integrated nanofibers shows that the rare earth is very well distributed into the polymer matrix. Also there is significant enhancement in the intensity of integrated nanofiber.

The copolymers consisting of acrylic and methacrylic esters have achieved prime importance due to their versatile environment friendly applications. Copolymerization of Methyl methacrylate (MMA) with suitable vinyl monomers such as alkyl acrylate and methacrylate has been carried out for modifying the properties of the polymer. In current research synthesis of waterborne copolymer of MMA and 2- Ethyl hexyl acrylate (2-EHA) carried out by ecofriendly emulsion polymerization technique and the kinetics of polymerization, characterizations of the copolymers have been studied. Synthesized copolymers were characterized by FTIR, NMR, DSC, and TGA. The kinetics results of the MMA-co-EHA copolymer was compared with the previously synthesized copolymer MMA with Butyl acrylate (BA). On comparing these results, it was found that EHA gives higher conversion with respect to BA under the same reaction conditions. Out of all the prepared latexes some are suitable for binder purposes in environment friendly water borne coating applications.

Two-hybrid products of bentonite intercalated carbohydrate polymers (chitosan ( BE.P.CH ) and 2- hydroxyethyl methacrylate/methyl methacrylate copolymer (BE/P.HEMA/MMA)) were synthesized as enhanced adsorbents for methyl parathion pesticide (MPP). The intercalation processes induced the affinity and the capacity of bentonite achieving the best value at pH 8. The maximum MPP adsorption capacities of BE (287.3 mg/g), BE/P.CH (634.5 mg/g), and BE/P.HEMA-MMA (868.5 mg/g) obtained after 300 min, 240 min, and 360 min, respectively. The kinetic properties of BE follow the Pseudo-second order behavior (R2 = 0.93) while BE/P.CH and BE/P.HEMA-MMA are of Pseudo-First order behavior (R2 > 0.92). Based on the equilibrium studies, the three products are of Freundlich isotherm behavior (R2 > 0.9) and the uptake is of multilayer forms on heterogeneous surfaces. The Gaussian energies (>8 KJ/mol), Gibbs free energies (>20 to 40 to

The present work has been carried out to understand the variations in a physical property that occur on insertion of a filler material in a polymer. Here, the authors report the synthesis and optical characterization of thin films of FeCl3 doped poly (methyl methacrylate) (PMMA). These films have been prepared by dispersing FeCl3 in different concentration (1%,2%,4%,8%) in PMMA using the solution casting technique. The thickness of the developed films is 100 μm. The optical properties of pure PMMA film and PMMA films doped with FeCl3 were investigated by recording the transmittance data on EI 2375 UV–VIS double beam spectrophotometer in the wavelength range 400–1100 nm. Results show that transmittance of the films decreases as the concentration of metal salt increases, attaining a minimum transmittance of 59% for 8 wt% of filler. This transmission data is further used to evaluate all other optical parameters like absorption coefficient (α), extinction coefficient (κ), refractive index (η), real and imaginary parts of dielectric constant (er andei), optical conductivity (σ) and skin depth (χ). The optical energy band gaps (Eg) have also been calculated.

Advancements and Ascendancy in the use of Poly (methyl methacrylate) (PMMA) polymer has uncloaked the broad applications in nanotechnological field. There is a requirement to converge these advances in terms of review article for better comprehension and easy approach with a special focus on optical and thermal property related issues. This review article provides accurate and deep understandings into the capabilities offered by the PMMA polymer when coupled with the different nanoparticles. Incorporation of different nanoparticles into host Poly (methyl methacrylate) (PMMA) can enhances the optical and thermal properties. These properties of the nanocomposites can be regulate by controlling the different parameters such as sample preparation techniques, type of solvent used, nanoparticles loading concentration, and nanocomposite film thickness. This review article also reveals optical and thermal properties of different nanocomposite films of PMMA/CuO, PMMA/ZnO, PMMA/TiO2 and PMMA/SiO2.

Nowadays, anticounterfeiting technology and information security by solvent-free photoluminescent polymeric latex nanoparticles are of considerable interest in variety of hi-tech systems. Herein and for the first time, Rhodamine B ethylenediamine acrylate (N-RhBAc) was synthesized and copolymerized with methyl methacrylate and glycidyl methacrylate to obtain epoxy-functionalized fluorescent latex nanoparticles (RhAcL-series) through emulsion polymerization. Inclusion of N-RhBAc into the spherical polyacrylic nanoparticles with average particle size of 40−70 nm enhanced its absorption intensity (λmax of 571 nm) and emission intensity (λem of 588 nm) up to 8 and 3.5-fold with respect to N-RhBAc in the solution state (λmax of 524 nm and λem of 582 nm), respectively. The nanometric size of particles and decorated epoxy functional groups on their outer layer provided well-wetting and fine-diffusion into the cellulosic nanofiber. To obtain anticounterfeiting inks with high-resolution marking on cellulosic paper without spreading and tracing, fluorescent RhAcL-1 was formulated with required thickening agent and defoamer. The painted pattern by the above ink could immediately be developed and illuminated with brilliant red-pink fluorescence emission upon UV irradiation.

The article presents the white light emission poly (methyl methacrylate) cylindrical fibre fabricated by co-doping by organic luminescent dyes. The used composition of aromatic hydrocarbon 1,4-Bis(2-methylstyryl) benzene Bis(MSB) and xanthene dye Rhodamine B (RhB) assures covering the emission in the range 370–700 nm under 355 nm excitation (Nd-YAG, third harmonic). The chosen complexes, according to the wide emission bands in the visible spectrum range and relatively large spectral shift of emission Bis(MSB) and absorption bands of RhB complexes, reduce the spectrum shape modification in the polymeric fibre structure and can be effectively used for lightning applications. The fabrication process and characterization of luminescent properties (emission spectrum, chromaticity CIE 1931 coordinates) vs. fibre length (0.5 m) are presented and discussed.

This work investigated the gamma-ray shielding performance, and the physical and mechanical properties of poly (methyl methacrylate) (PMMA) composites embedded with 0–44.0 wt% bismuth trioxide (Bi2O3) fabricated by the fast ultraviolet (UV) curing method. The results showed that the addition of Bi2O3 had significantly improved the gamma shielding ability of PMMA composites. Mass attenuation coefficient and half-value layer were examined using five gamma sources (Cs-137, Ba-133, Cd-109, Co-57, and Co-60). The high loading of Bi2O3 in the PMMA samples improved the micro-hardness to nearly seven times that of the pure PMMA. With these enhancements, it was demonstrated that PMMA/Bi2O3 composites are promising gamma shielding materials. Furthermore, the fast UV curing exerts its great potential in significantly shortening the production cycle of shielding material to enable rapid manufacturing.

In this investigation, we have developed a new semiconductive Polymeric Transparent Matrix (PTM) as a substitute to the glass substrate used in a conventional optoelectronic device. Initially, we have synthesized Poly(methyl methacrylate) (PMMA) and series of its copolymers with Styrene in different weight percent (wt.%) ratio via solution polymerization process. The obtained polymers were characterized using various techniques to understand the effect of introducing different proportions of Styrene comonomers on PMMA backbone. The optimum composition of PTM was chosen based on copolymer’s mechanical properties, optical transparency, and ultraviolet (UV) shielding properties. Then, a series of nanocomposites consisting of optimized PTM and various wt.% of Multiwalled Carbon Nanotubes (MWCNT) as a conductive filler were fabricated to increase the conductivity of PTM. A steep increase (109 fold) in bulk electrical conductivity was observed in case of 0.25 wt% MWCNT loaded optimized composite matrix, along with the retention of a good amount of optical transparency (88% at 550 nm) and 100% UV-C shielding. This optimized nanocomposite has also shown amelioration in mechanical properties as a result of uniform dispersion of MWCNT. These remarkable attributes favor the use of this optimized semiconducting PTM as a potential transparent substrate for next-generation organic optoelectronic devices.

The oxidative cross-coupling of unsaturated aldehydes and alcohols with methanol is catalyzed by O-activated gold surfaces in both ambient pressure and UHV conditions. From liquid-phase studies it has been found that either the addition of a base or the use of a basic support is necessary for high yields of the corresponding methyl ester. Here we demonstrate that addition of a small amount of Ni, at the single atom limit, on supported Au nanoparticles, without the aid of a base in the reaction solution or the use of a basic support, is sufficient to activate Au for the selective oxidative esterification of methacrolein with methanol. The Ni concentration and dispersion are followed by ICP-AES and in situ DRIFTS, respectively. The active site appears to be the same for both NiAu and Au NPs; namely, an [Au-Ox]- species, as similar apparent activation energies of the reaction were found in kinetic studies over these two catalysts. Ni was also shown to allow for lower methanol concentrations to be used without affecting the catalytic activity and selectivity to the desired product, methyl methacrylate. In situ vibrational spectroscopy studies were conducted in an ATR-IR cell, where the reaction progress was monitored by detecting the gradual conversion of adsorbed reactants on the catalytic surface to intermediates and finally to the desired product, which was produced at close to 100% selectivity at conversions exceeding 25% at 60 ℃ on NiAu single atom alloy nanoparticles.

Due to the “trade-off” effect between the high water adsorption and low stability under high Relative Humidity of polymer matrix, fabrication of resistive-type polymer-based humidity sensors with a wide impedance response and excellent stability in high relative humidity remains a great challenge. Aim at solving that, a novel polymeric humidity sensing matrix, specifically a tadpole-shaped, polyhedral oligomeric silsesquioxane (POSS) containing block copolymers (BCPs) of POSS-poly(methyl methacrylate)-polystyrene (POSS-PMMA-SPS) were proposed. This novel BCP was synthesized using atom transfer radical polymerization (ATRP) employing a two-step approach, and following post sulfonation, a series of sulfonated BCPs (POSS-PMMA-SPS) with different sulfonation degree was obtained. The subject humidity sensors were produced using different sulfonated BCPs employing a dip-coating technique, and three wide-impedance response humidity sensors were produced. Each of these sensors exhibited an excellent humidity-sensing response of more than 104 within the humidity range from 11% to 95% RH. In particular, the humidity sensor S-6 that had a proper degree of sulfonation presented a relatively fast response (t90% of 11 s and 80 s in both the water adsorption and desorption processes), and superior repeatability for more than 30 days.

We synthesized 6-arm star-shaped polystyrene-ran-poly(methyl methacrylate) copolymers ((S-r-M)6) for mechanically robust and thermally stable ion gels containing an ionic liquid of 1-ethyl-3-methylimidazolium bis(trifluoromethyl sulfonyl)imide ([EMI][TFSI]). The (S-r-M)6-based gels exhibited higher elastic modulus (E ∼ 1.67 × 105 Pa), which is more than five-times that (∼0.29 × 105 Pa) of linear PS-r-PMMA-based ion gels at the same Sty content (∼29 mol%), irrespective of applied mechanical strains (stretching and compression). In addition, they showed outstanding thermal stability. For example, the gel-sol transition temperature (Tgel) of (S-r-M)6 gels was ∼72 °C, compared with that (∼56 °C) of linear PS-r-PMMA-based ion gels. These physical properties of gels were further improved by increasing total molecular weight and the fraction of styrene, giving E of ∼3.8 × 105 Pa and Tgel of ∼163 °C. The resulting gels were functionalized by introducing electrochemiluminescence luminophores (tris(2,2′-bipyridyl)ruthenium(II) hexafluorophosphate). By utilizing the mechanical robustness of the (S-r-M)6 gels, we fabricated emissive electrochemical displays through ‘cut-and-stick’ process. Moreover, the thermally stable (S-r-M)6 gels indicated good dimensional stability, offering a chance to demonstrate ECL devices that operate even at high temperatures.

Hypothesis The CO2-sensitive dispersion/precipitation transition of polymer latexes fabricated based on a responsive emulsifier is a promising way to conveniently acquire bulk polymer materials. Nevertheless, the tedious synthesis procedures for switchable surfactants and the harsh operating requirements for the sensitive latexes constrain the applicability of the approach for latex preparation. Therefore, a new strategy for generating latexes with tunable CO2 responsiveness in a maneuverable way is urgently needed. Experiments In this work, a CO2-switchable electrostatic interaction is introduced to construct responsive latexes. A series of lightly crosslinked poly(diethylaminoethyl methacrylate-styrene) [P(DEA-St)] latexes with different PDEA contents were fabricated via one-pot emulsion copolymerization, with divinylbenzene and sodium dodecylsulfate (SDS) used as the crosslinker and anionic emulsifier, respectively. The influence of the DEA feeding ratio on the resulting P(DEA-St) colloids was characterized by Fourier transform infrared spectroscopy and scanning electron microscopy. Then, a cyclic CO2/N2 input was introduced to verify the response transitions of polymer latexes. Findings Accompanied by the stepwise decrease of DEA feeding ratio, the morphology of the resulting copolymerized nanoparticles changed from an ambiguous bulge to the typical spherical pattern. In addition, the P(DEA-St) latexes treated by cyclic CO2/N2 exhibit four different types of response modes, namely (i) CO2-switchable swelling/deswelling transition, (ii) CO2-reversible dispersion/coagulation transition, (iii) CO2-induced irreversible destabilisation and (iv) CO2-insensitive latexes. The CO2-responsive destabilisation is highly applicable in the separation and transportation fields of commercial latex products, such as poly(methyl methacrylate), poly(n-butyl acrylate) and poly(butyl methacrylate) colloids.

Hollow silica particles are desirable for numerous applications, however, designing hollow silica materials with varying hollow structures and shapes remains a significant challenge. Herein, a strategy for the precisely controlled synthesis of hexagonal-shaped hollow silica plate (HHSP) particles was successfully prepared via a sol-gel method at room temperature, using tetraethyl orthosilicate (TEOS) as a silica precursor and zinc oxide (ZnO) particles as a colloidal template. The effect of reaction time was carried out to control the structure and morphology of HHSP particles, and the thickness of silica shell can be tuned in the range from 12.2 to 43.2 nm by adjusting the TEOS/ZnO molar ratios. In addition, the polymer/HHSP composite thin films were prepared using poly(methyl methacrylate) (PMMA) matrix and surface modified HHSP particles by grafting silane coupling agents. High transmittance values were observed (>95%) for the composite thin films (5 μm in thickness, 0.1–1.0 wt% HHSP) in the ultraviolet and visible regions. Furthermore, the refractive index of HHSP particles was observed to be 1.28, which is significantly lower than dense silica (n = 1.46). These results suggest that the approach adopted herein will open up opportunities for the development of a new generation of film materials with a low refractive index.

Much attention has been devoted to disposing traditional-sized poly(methyl methacrylate) (PMMA) waste by pyrolysis for methyl methacrylate (MMA). The pyrolysis of micron-sized PMMA waste, which may be different from that of traditional-sized PMMA waste, received little concern. The present study investigated the kinetics and volatile products of micron-sized PMMA waste pyrolysis in inert atmosphere using thermogravimetry and Fourier transform infrared analysis. A global optimization algorithm namely Shuffled Complex Evolution (SCE) was employed to simultaneously optimize the kinetic parameters. Results indicated that one shoulder and one peak occurred in the MLR variations with temperature. The values of the MLR at the shoulder and peak, the average MLR all increased with the heating rate. The optimized kinetic parameters by SCE can be utilized to well reproduce the experimental thermogravimetric data. The values of activation energy and natural logarithm of pre-exponential factor were in the range of 235.95–248.61 kJ/mol and 16.96–28.76 min−1, respectively. The value of activation energy of micron-sized PMMA waste pyrolysis under the present study was greater than that of the traditional-sized PMMA pyrolysis in the previous studies. MMA and CO2 were the major volatile products generated from the micron-sized PMMA waste pyrolysis. The volatile products yield at peak was much larger than that at shoulder. The MMA and CO2 yield were in the range of 87.98–93.54% and 6.46–12.02%, respectively. High MMA yield may be obtained from the pyrolysis of micron-sized PMMA waste in inert atmosphere by appropriately increasing the heating rate adopted in the reactors in the practical applications.

Carboxybetaine methacrylate (CBMA), which has anti-biofouling properties, was incorporated into poly(methyl methacrylate) (PMMA) to prevent multi-species biofilm formation without impairing the critical mechanical properties of the PMMA. The incorporation of 2-methacryloyloxyethyl phosphorylcholine (MPC, 3 wt%) was used as a positive control. PMMA wettability was found to increase with increasing CBMA content. The addition of CBMA resulted in decreased mechanical properties of PMMA. The incorporation of 3% CBMA into PMMA resulted in considerable long-term anti-biofouling effects that reduce adhesion of various fungi, bacteria (Candida albicans, Actinomyces naeslundii, and Veillonella parvula), and a human saliva-derived biofilm. The anti-biofouling effect of CBMA-incorporated PMMA surpassed that of the positive control. By calculating the intensity of the collective band using Raman spectroscopy, CBMA was proven to form the most stable hydration layer. Neither CBMA nor MPC groups showed cytotoxicity. Occlusal splints fabricated using 3% CBMA showed clinically acceptable aesthetic properties with slight turbidity. Despite a limitation in terms of deteriorations of the mechanical properties, the addition of an appropriate amount of CBMA to PMMA inhibited the attachment of fungi and bacteria and suppressed multi-species biofilm growth. The aesthetic properties of CBMA-incorporated PMMA are acceptable for clinical practice.

In the presented study poly(methyl methacrylate) (PMMA) and magnetite nanoparticles were used to prepare novel PMMA/Fe3O4 electrospun nanofibers. The obtained materials were characterized, and then modified and used as supports for covalent binding and encapsulation of laccase from Trametes versicolor. High enzyme loading (63.2 mg of laccase per 1 cm2 of support) was recorded for the system after covalent binding, and the formation of stable interactions was confirmed, as leaching of the enzyme from the support did not exceed 12%. Furthermore, the obtained biocatalytic systems exhibited excellent pH, thermal and storage stability as well as reusability: after 40 days of storage and 5 successive biocatalytic cycles they retained 80% of their initial properties. Experiments on the removal of antibiotic showed that both immobilized laccases possess high ability to convert tetracycline. Under optimal process conditions (pH 5, temperature 25 °C, tetracycline solution concentration 1.0 mg L−1) the removal efficiency reached 100% and 94% for covalently bonded and encapsulated laccase. Finally, the degradation products were examined to investigate the degradation mechanism. The data showed that oxidation, dehydrogenation and demethylation are major reactions in the degradation of tetracycline using immobilized laccase. The findings demonstrate clearly that laccase immobilized by covalent binding and encapsulation using electrospun materials has the potential for application in environmental protection processes for the removal of antibiotics.

In this paper, an impedance-transduced sensor is developed based on a nanostructured graphene (GN) and poly (methyl methacrylate) (PMMA) sensing film for the detection of individual volatile organic compounds (VOCs) in aqueous media. Benefiting from a porous and high surface area, the nanostructured nanofiber is characterized by scanning electron microscopy (SEM) and optimized by the electrochemical impedance spectroscopy (EIS) technique. The recorded EIS data indicate the selective recognition of four VOCs of interest at a constant pH while there is no redox probe. The non-faradaic responses to each analyte at different concentrations are correlated with a three-element equivalent circuit (resistances of the solution and the film, and a pseudo-capacitance). To analyze the ability of the sensing film in distinguishing between VOCs with similar average boiling points, the values of the individual equivalent circuit elements are used as features and clustered in three-dimensional (3D) plots. Among the features, the two representing the maximum differences between the VOCs are represented in a two-dimensional (2D) plot to show the selectivity of the sensor. The feature extraction analysis demonstrates that the constant phase element (CPE) of the equivalent circuit is a more accurate predictor of VOCs than the interfacial capacitance. These results show high selectivity of the sensorial platform due to the synergistic pairing of nanostructured GN and PMMA.

International audience; Smart emissive materials that can react to external stimuli in a reversible way are challenging to develop and have been the subject of considerable interest. Here, we present a printable hybrid material that can withstand numerous writing-erasing cycles. This material is based on a poly(methyl methacrylate) host matrix embedding by copolymerization of a red NIR phosphorescent metal cluster and a blue green 3-oxindole emitter. Irradiation of the homogeneous and stable hybrid films changes the emission color from white to deep red because of the oxygen perturbed energy transfer from the organic dye to the metal cluster. Because of the low PMMA gas permeability, encrypted data lifetime can be tuned from minutes to days, can be self-erased, and be rewritten at will. This material represents a key stepping stone for anticounterfeiting, optoelectronic, data recording, and many other technologies © 2019 Elsevier Ltd

Current lithium metal batteries are haunted by stability issues and safety concerns that are critically linked to the growth of dendritic lithium. A quasi-solid electrolyte is designed that is non-flammable and is capable of suppressing dendrites by in-situ polymerizing a poly (methyl methacrylate) skeleton to support phosphate-based electrolytes with high salt concentrations. By varying the polymer-to-electrolyte ratio, we reveal that there is a strong interplay between the mechanical strength, the ionic conductivity, and the ability to suppress dendrites. A carefully chosen composition leads to a quasi-solid electrolyte with a high ionic conductivity of 0.11 mS cm−1, a wide electrochemical window up to 4.8 V vs. Li/Li+, and the ability to suppress lithium dendrites at high current densities. Stable lithium plating and stripping is achieved using such electrolyte at a current density of 1.2 mA cm−2, a two-fold increase compared with its liquid counterpart. A lithium-metal battery using a LiFePO4 cathode with a high active material loading of ~15 mg cm−2 based on the quasi-solid electrolyte is demonstrated which exhibits high specific capacity of over 100 mAh g−1 and is able to be cycled 150 times without obvious capacity decay. The current work offers a practical solution to the safety concerns as well as the stability issues of lithium metal batteries.

Recyclable low-temperature phase change microcapsules (LTPCMs) have the potential applications in the short-distance cold chain transportation due to their reliable reusability in cold storage. Herein, LTPCMs are synthesized via in-situ suspension copolymerization of styrene and methyl methacrylate in absence of harm substances, providing the non-crosslinking copolymer shells. n-Dodecane, n-tridecane and n-tetradecane, inducing the microphase separation of non-crosslinking copolymers, are successfully encapsulated to achieve n-do-LTPCMs, n-tri-LTPCMs and n-tetra-LTPCMs, which respectively bear the high phase change enthalpy of 110.53 J·g−1 at −8.69 °C, 38.33 J·g−1/93.71 J·g−1 at −17.61 °C/−4.96 °C and 166.79 J·g−1 at 8.59 °C and subsequently show the cold-discharging periods of 30 min, 40 min and 120 min. The multiple circulation of cold-discharging process indicates the excellent recyclability for cold storage owing to their unchanged cold-discharging period. Especially, n-tetra-LTPCM-65 bears the best comprehensive cold-storing performance in all the previously reported LTPCMs, such as narrow cold-discharging temperature range of 3–4 °C, long cold-discharging period of 69–120 min and low cold-discharging capacity of 33.4 J·g−1·K−1. This work successfully provided the recyclable LTPCMs for cold storage in the short-distance cold chain transportation.

Due to intermediate hydrophobicity of methyl methacrylate (MMA) monomer in water, it is difficult to prepare its stable water in oil high internal phase emulsion (HIPE). Moreover, the addition of fully hydrophilic co-monomer such as 2-hydroxyethyl methacrylate (HEMA) in MMA monomer makes it further troublesome to stabilize these emulsions. This paper addresses the preparation of such type of difficult to prepare emulsions via addition of an amphiphilic fluorinated di-block copolymer (FDB), poly(2-dimethylamino)ethylmethacrylate-b-poly(trifluoroethyl methacrylate) (PDMAEMA-b-PTFEMA) as stabilizer. Interestingly, HEMA and/or HFBA (hexa fluorobutyl acrylate) as co-monomers were successfully added to impart some special properties such as thermodynamic stability, desired amphiphilicity to the final polyHIPEs. Fluorinated blocks in FDB anchored well at oil/water interface of HIPE, offering enough hydrophobicity to the comparatively hydrophilic monomers and in turn providing resistance against coalescence. MMA polyHIPEs were found to be fully hydrophobic just by replacing HEMA co-monomer with HFBA. Due to superb inherent hydrophobic nature of fluorine atoms, MMA-HFBA polyHIPEs showed remarkable water contact angle of 139°. Furthermore, the addition of fluorinated co-monomer in MMA based HIPEs significantly improved thermal stabilities of these materials with improvement in degradation temperature from 305 °C to 360 °C. Keywords: MMA, Porous polymers, Hydrophilic polyHIPE, Hydrophobic polyHIPE, Fluorinated di-block copolymer, RAFT

Thermal atomic force microscope (AFM) nanolithography enables many nanofabrication applications, but it requires special thermal probes. In this paper, we developed a vibration-assisted sample heating approach to implement the nanomachining of poly(methyl methacrylate) (PMMA) with a regular AFM probe with low stiffness (~0.16 N/m). The joule heating softens the PMMA, which lowers the normal force. The in-plane vibration with high frequency was applied to reduce the adhesion force between the AFM tip and the PMMA with elevated temperature, which enhances nanomachining performances. By using this approach, uniform nanopatterns with controllable dimensions were fabricated on PMMA films with small setpoint force.

The aim of the current study was to present a simple method for the fabrication of quantum dot (QD)/polymer films for possible use as a luminescent material in medical applications. To this aim the poly(methyl methacrylate) (PMMA) polymer matrix was modified in order to host Zinc Copper Indium Sulfide encapsulated by an outer core of Zinc Sulfide (ZnCuInS/ZnS) QD nanocrystals, through dispersion. Four composite PMMA films of ZnCuInS/ZnS nanocrystals with maximum emission at 530 nm and concentrations of 1.0, 4.0, 6.0 and 10.0 %w/v, were prepared. X-ray irradiation and scanning electron microscopy (SEM) micrographs were used to evaluate the volume homogeneity of the final samples, as a measure of QD dispersion. The coefficient of variation (CV) estimated from homogeneity measurements, increased with increasing concentration, for the 1.0, 4.0 and 6.0 %w/v samples. The minimum CV value was obtained for the 10.0 %w/v sample which is attributed to the incorporation of sonication in the final product, during the fabrication process. Homogenous dispersion was observed from the SEM micrographs.

Poly (methyl methacrylate) (PMMA) is a hard and brittle thermoplastic. Thus, its application is limited. PMMA-modified natural rubber (MNR) is a NR derivative which was synthesized in the laboratory. MNR has lower glass transition temperature, Tg as compare to PMMA. This research utilized the modified dynamic vulcanization which rubber was separately compounded with curatives by using a two-roll mill and the resultant rubber compound was added into PMMA during melt mixing. This technique effectively reduces the limitation of the mixing rate and dispersion of curatives in both the thermoplastic and elastomer components can be improvement. The blend of PMMA/MNR is expected to produce a physical blend with better mechanical properties at optimum melt mixing parameters. Based on investigation done for different parameters (processing temperature, shear rate measured via rotor speed and total missing time), the recommended melt mixing parameters are given at processing temperature of 200 °C, rotor speed of 50 rpm and total mixing time of 8 min. This technique produces blends with optimum properties, as opposed to prolonged shear technique which produce negative effect to PMMA/MNR blend.

Nanofibers are gaining much importance in research field owing to its versatile applications and unique properties. Eventhough different methods are there to fabricate nanofibers; electrospinning is of great interest due to its added advantages in terms of cost effectiveness and wide applicability. Among different materials electrospun polymers are more preferred because of no post-processing requisites. The major challenge associated with electrospinning is to optimize the parameters determining the fineness of surface morphology of electrospun fibers. In the present study an attempt is made to investigate the effect of solution parameters such as concentration of the polymer solution, nature and ratio of solvent type and the processing parameters like applied voltage on the fineness of fiber surface morphology of copolymer poly(styrene-co-methyl methacrylate) fibers. The effect of fiber diameter on thermal degradation is monitored. The concentration studies were done by varying the concentration from 3% (w/v) to 20% (w/v) and for solvent studies varying proportions of THF and DMF were chosen. Voltage studies were carried out by varying the applied voltage from 15 kV to 25 kV. The characterization techniques include SEM, TGA UV–Visible Spectroscopy and FTIR analyses. The results showed that by adjusting the applied voltage, concentration of the polymer and solvent ratio, a good control over the fineness of surface morphology can be accomplished. From the TGA analysis it is found the degradation property of nanofibers varied as a function of fiber diameter.

The aim of this study was to encapsulate ivermectin in poly(methyl methacrylate) (PMMA) using a supercritical antisolvent (SAS) process. The Box–Behnken method was employed for obtaining a lower average particle diameter (dexp) of ivermectin-impregnated PMMA nanoparticles. The encapsulation efficiency was 73.08 ± 3.22%, and the nanoparticles were characterized morphologically, thermally, and conformationally using the following techniques: scanning electron microscopy, differential thermogravimetric analysis, and attenuated total-reflectance Fourier-transform infrared spectroscopy. The in vitro release kinetics showed that the drug had a controlled release of approximately 100 h, and that the Higuchi, Peppas–Sahlin, and Korsmeyer–Peppas models were able to correctly describe the drug diffusion processes. The precipitation kinetic parameters were determined from dexp using the population balance equation. This equation showed that the nucleation rate and nucleation population density were dominant for R6 (9 MPa, 313.15 K, 3 mL/min), and that the growth rate had little variation across all experiments.