Methyl Methacrylate Butyl Acrylate Research Articles

Construction of Steady Amorphous Colloidal Array Patterns via Infiltration-Driven Assembly of Core-Shell Microparticles followed by Short-Time Heating.

Although core-shell microparticles with a hard core and soft shell are often used to fabricate photonic crystal films, they are rarely applied to construct steady amorphous colloidal array (ACA) patterns. In this work, a series of monodisperse core-shell microparticles with a polystyrene (PS) core and poly(methyl methacrylate-butyl acrylate) (P(MMA-BA)) shell have been successfully synthesized, and the glass transition temperatures (Tg) of the shell layer have been well regulated. The synthesized core-shell microparticles were then used to fabricate ACA patterns via a convenient infiltration-driven assembly method. The results showed that the Tg of the shell significantly affected the microstructure of the amorphous colloidal arrays (ACAs). During the assembly process, the microparticles quickly contacted each other and the lower-Tg shells could merge with each other to form a continuous film. In this situation, the PS core was embedded and ranked in the P(MMA-BA) film, and both the refractive index contrast and order degree of the colloidal array became relatively low, resulting in a poor structural color. However, when the Tg of the shell layer was moderately high, a short-range ordered array was prepared via infiltration-driven assembly, thereby displaying a bright structural color. More importantly, the shell layers could merge with each other to some extent after short-time heating, resulting in fine mechanical stability. In brief, this study provides a facile and environmental approach to construct steady ACA patterns, which is promising in printing and painting industries.

Coagulative Nucleation in the Copolymerization of Methyl Methacrylate-Butyl Acrylate under Monomer-Starved Conditions.

Coagulative nucleation in the copolymerization of methyl methacrylate-butyl acrylate (MMA-BA) via semicontinuous emulsion heterophase polymerization (SEHP) under monomer-starved conditions in latexes with high solid content (50.0 wt %) and low concentrations of surfactant is reported. The SEHP technique allows the obtention of latex with high colloidal stability and has potential industrial application in polymer synthesis. High instantaneous conversions (>90%) and a high-ratio polymerization rate/addition rate (Rp/Ra) ≥ 0.9 were obtained at low times until the final copolymerization, which confirmed the starved conditions in the systems at the highest surfactant concentrations. The particle size exhibited a linear size increment at conversions between 0 and 40% induced by homogeneous nucleation, a transition region between 40 and 50%, and non-linear behavior at higher conversions by coagulative nucleation. These three behaviors were also observed in the particle surfactant coverage area (Sc), Z-potential, particle coagulation rate (dNp/dt) by the Smoluchowski model, final particle size (Dpz), and number particle (Np) through the reaction. By means of transmission electron microscopy (TEM) images, the onset of coagulation was observed from 50% of conversion until the end of the reaction. In addition, in both processes of copolymerization, tacticity was displayed (mainly syndiotacticity).

Preparation and performance of durable waterproof adhesive layer for steel bridge deck based on self-stratification effect

In view of the shortcomings of the existing steel bridge deck waterproof adhesive layer (WAL), such as poor durability, high construction cost and long construction period, a new preparation method of waterproof coating with self-stratification effect is proposed. In this paper, poly butyl acrylate-methyl methacrylate–styrene block copolymer with lower glass transition temperature was synthesized by free radical solution polymerization, and 5 kinds of self-stratification coatings were obtained by mixing it with epoxy resin at different mass ratios. The glass transition temperature, thermal stability and chemical composition of acrylic resin were characterized by DSC, TGA, and FT-IR. The self-stratification behavior of the coatings was confirmed by FT-IR, SEM, and water contact angle test. The basic performance and road performance of above self-stratifying waterproof coatings were tested according to specific standards. The results show that these coatings exhibit excellent heat resistance, low temperature flexibility and mechanical properties, namely, average tensile strength can reach 6 MPa, the elongation at break can reach 108 %. Furthermore, the coatings also present extraordinary pull-out strength of 9.51 MPa and excellent water impermeability. Moreover, the tensile strength and elongation at break of the self-stratifying waterproof coatings after UV aging test decreased by 7.3 % and 5.2 %, respectively, indicating that above coating have excellent durability. Therefore, the performance of the coating prepared in this paper fully meets the requirements of the road and bridge waterproof coating standards. The optimum mixing ratio of acrylic resin and epoxy resin is recommended as 3:7 based on their performance. Finally, self-stratifying mechanism of coatings was proposed based on the surface energy theory, which provides theoretical support for the design and preparation of the steel bridge deck WAL.

Preparation of Janus structural color sheets with flexibility, stability and low angle dependence based on textile

Structural colors with low angle dependence arising from photonic crystals are of increasing interest in various fields, such as sensing and display. In this study, the composite Poly(styrene-methyl methacrylate-acrylic acid) photonic crystals consisting of amorphous, simple cubic and face-centered cubic structures were facilely constructed by vacuum-assisted filtration self-assembly. Interestingly, this method enables microspheres to be assembled on flexible fabrics in a "bottom-up" manner, and different types of structural color sheets (single-sided coloring, double-sided homochromy or heterochromatic) can be obtained by controlling the dosage and particle size of the microspheres. In particular, the prepared structural color sheets are exceptionally bright and have low angle dependence. Subsequently, the photonic crystals in the flexible fabric were reinforced by the introduction of Poly(methyl methacrylate-butyl acrylate), which resulted in a significant improvement in the mechanical stability, the performance of which was demonstrated by water-rinsing, friction and folding tests. This study provides a novel way to prepare new structural color materials with bright and low angle dependence. In addition, this double-sided heterochromatic structural color sheet has potential applications in the display field.

Polystyrene@poly(methyl methacrylate-butyl acrylate) Core–Shell Nanoparticles for Fabricating Multifunctional Photonic Crystal Films as Mechanochromic and Solvatochromic Sensors

Responsive photonic crystals (PCs) with a nanoscale band gap assembled by colloidal nanospheres have been increasingly utilized in detection and sensing devices owing to their attractive ability to change color in response to external conditions. However, most of the reported works have been dedicated to single-functional PCs, which can only be used as sensors or detectors in a specific situation. Thus, producing a multi-functional PC for various industrial applications remains a challenge. In this work, multi-functional soft PC films (SPCFs) with a brilliant structural color and a robust structure are fabricated by using polystyrene@poly(methyl methacrylate-butyl acrylate) [PS@P(MMA-BA)] nanospheres with size in the range of 200–350 nm as building blocks. The SPCFs possess both the mechanochromic and solvatochromic properties owing to the adjustable photonic band gap under stress and polar solvent conditions. The mechanochromic effect of the SPCF under stretching results in a blue shift of the structural color due to the decrease in lattice spacing. In contrast, the solvatochromic mechanism of the SPCF is that it can be swollen by polar solvents, resulting in the increase in the lattice spacing of PCs and a red shift of the structural color. Meanwhile, the SPCF can keep its original structural color while stretched for 20 cycles or when the organic solvent is completely evaporated. Therefore, robust multi-functional SPCFs fabricated by the self-assembly of PS@P(MMA-BA) nanospheres under gravity sedimentation can respond to stress and organic solvents, showing great potential for use in sensors and detectors.

Amine-Containing Resin for Coating with Excellent Formaldehyde Removal Performance

Formaldehyde (HCHO) is known to be a strong carcinogen, widely present in construction substances. To remove HCHO in the environment, we propose to graft organic amines to the chains of resins used in coatings, and when the indoor walls are coated by the materials containing such resins, HCHO can diffuse from the environment into the coatings to react with amines through irreversible nucleophilic addition. Specifically, we have introduced diallylamine (DA; as a comonomer) in poly(methyl methacrylate–butyl acrylate–methacrylic acid) (PMA) to form the DA–PMA resins through emulsion polymerization. It is found that the films formed from the DA–PMA resins with the mass fraction of DA from 1 to 5% can effectively remove HCHO. The largest average rate in HCHO removal has reached 0.198 mol h–1 kg–1 in the case of DA–PMA with 5% DA. In addition, the introduction of DA is able to improve the colloidal stability of DA–PMA particles, and the smoothness of the DA–PMA films is rather similar to that of pure PMA. Because of the cross-linking role of DA, the thermal stability of the DA–PMA polymers has been significantly improved with respect to pure PMA. It should be noted that a similar amine-containing resin was prepared using N,N′-methylenebis(2-propenamide) as the comonomer, but it did not perform as well as that made with DA. Proper theoretical (density functional theory) calculations provided an explanation and might enable one to predict in advance whether other related calculations might, or might not, work.

Graphene Oxide/Reduced Graphene Oxide Enhanced Noniridescent Structural Colors Based on Silica Photonic Spray Paints with Improved Mechanical Robustness.

In contrast to traditional pigment colors, structural colors have developed a great potential in practical applications, thanks to their unique nonfading and color tunable properties; especially amorphous photonic structures with noniridescent structural colors have attracted considerable attention and their applications have expanded to more fields. Herein, graphene oxide (GO) and reduced graphene oxide (RGO) enhanced noniridescent structural colors with excellent mechanical robustness were established by a time-saving approach named spray coating, which allows for rapid fabrication of angular independent structural colors by spraying different photonic spray paints (PSPs) to ensure color multiplicity that was adjusted by the silica nanoparticles (SiO2 NPs) sizes onto the substrates. The incorporation of poly(methyl methacrylate-butyl acrylate) (PMB) improved the adhesion existing among SiO2 inter-nanoparticles and between SiO2 NPs and the substrates, taking advantages of the low glass transition temperature () of butyl acrylate derivative polymer and made PMB embedded PSPs coated patterns being imparted with good mechanical robustness and abrasive resistance. The peculiar light adsorption of GO and RGO across visible light spectrum facilitate higher color saturation. The improvement in color saturation of GO and RGO doped PSPs is expected to boost the promising applications in structurally colored paintings, inks and other color-related optical fields.

Design of VO2-based photoactuators for smart windows

Smart windows can slow down the heating rate in buildings to a certain extent and realize energy savings and emission reduction. Various approaches have attempted to make windows ‘smart’ by tailoring their thermal insulation behavior in response to environmental changes. However, there is still room for further improvement in their efficiency and automation performance. Here, based on photothermal functional fillers and shape memory substrates, a new type of photoactuator for smart windows—passively controlled shuttering—was designed. The photoactuator was composed of VO2@SiO2 and methyl methacrylate butyl acrylate polymer (MBP). These two functional components had similar transition temperature (30 °C), and the photothermal conversion of VO2@SiO2 stimulated the shape memory behavior of the composite. It was demonstrated that the intelligent performance was closely related to the shape memory properties of MBP and the phase transition characteristics of VO2 NPs, which synergistically modified the solar regulation ability. The results suggest that this new type of optical driving window has potential applications in the field of wearable sensors, energy conservation and medical devices.

Synthesis of organic‐inorganic hybrid nanocomposites based on the acrylate monomers and investigation of scratch resistance of these nanocomposites

AbstractOrganic‐inorganic hybrid nanocomposites can be used as polymer coatings in order to improve their scratch resistance. These nanocomposites consist of a polymer matrix that provides flexibility and lightweight, and inorganic nanoparticles that are responsible for high thermal stability and improving scratch resistance. In this study, the polymer matrix, methyl methacrylate‐butyl acrylate (MMA‐BA) copolymer, was synthesized by conventional emulsion polymerization. To get the highest conversion percentage of the copolymer, various parameters, including reaction temperature, weight ratio of monomers, mechanical stirrer speed, type and amount of initiator, total amounts, and weight ratio of emulsifiers were investigated. For the synthesis of nanocomposites, nanoparticles of titanium dioxide, iron oxide, silver sulfide, and modified and unmodified nanosilica were added to the copolymer with the highest conversion percentage. According to the data, the best conditions for the synthesis of a copolymer with the highest conversion percentage were as follows: weight ratio of MMA:BA = 60:40 with a total amount of 10 g monomers, mechanical stirrer speed of 250 rpm, thermal initiator water‐soluble ammonium persulfate with amount of 0.12 g, emulsifiers such as sodium dodecyl sulfate and Triton X‐100 with a weight ratio of 1:3 and a total value of 1 g, and the reaction temperature of 80°C. According to the results of thermal gravimetric analysis, the samples with the highest thermal stability were selected for nanoscratch test. Nanoscratch test results suggested that Ag2S nanocomposite including 0.03 g AgNO3 and 0.0072 g thiourea had the highest scratch resistance with the lowest coefficient friction (0.48) and the lowest coefficient scratch (0.113 μN–1/2). Chemical structures of synthesized compounds were confirmed by Fourier transform infrared spectroscopy. The morphology of synthesized Ag2S nanocomposite was investigated by scanning electron microscopy and energy dispersive X‐ray spectroscopy analyses.

Preparation of zinc methacrylate-methylmethacrylate-butyl acrylate emulsions and their application in exterior paints

Semi-batch emulsion polymerization of methyl methacrylate-butyl acrylate- methacrylic acid monomers were carried out with the addition of nano ZnO to the monomer feed, to obtain a binder for exterior architectural paints. Nano ZnO reacted spontaneously with acid groups to form zinc methacrylate or dimethacrylate which participated in crosslinking reactions. The amount of nano ZnO added was increased up to the equivalence point and in several cases exceeded for unmodified, hydrophilic or hydrophobic silane modified nano zinc oxides. The emulsions and clear polymer films obtained from them were characterized with conventional methods. FTIR and UV/Vis spectra confirmed the transformation of nano zinc oxide up to the equivalence point.The emulsions were used for preparing of opaque and transparent colored paints which were tested with UV exposure-condensation accelerated weathering along with clear polymer films. The color parameter, gloss and water contact angle changes were determined for every 250 h up to 1000 h. Optical microscopy and for some cases AFM, FTIR and FESEM were also used for further characterizations. Presence of zinc methacrylate crosslinking and in some cases, additional presence of nano ZnO, provided blistering prevention and improvement of gloss and color stability.

Preparation and characterization of the acrylic latex-laminating adhesives applied in BOPP/PE composite films

Acrylic latex-laminating adhesives (ALLAs) were successfully prepared via the monomer-starved seeded semi-continuous emulsion copolymerization with butyl acrylate–methyl methacrylate–acrylamide (BA–MMA–Am) monomers, and only 1.1 wt% emulsifier contents were employed. The effect of Am on final latex, the dried latex films, and adhesive properties of ALLAs were discussed by utilizing rotational viscometer, dynamic light scattering, transmission electron microscopy, Fourier transform infrared spectrometer, contact angle, differential scanning calorimeter, thermogravimetric analysis (TG), and mechanical experiments, respectively. The results indicated that the peel strength of the biaxial-oriented polypropylene/polyethylene composite films can reach a peak (3.15 N/15 mm) at the content of 2 wt% Am in the pre-emulsion feed, which satisfies an acceptable minimum peel strength (0.8 N/15 mm) for application. Additionally, average particle size of the final latex experienced few changes, but the particle size distribution of the latex changed notably as Am contents varied from 0 to 10 wt%, while Tg of ALLAs increased gradually, and the molecular weight (Mn and Mw) increased obviously. TG results showed that the ALLAs have excellent thermal stability with a high decomposition temperature of 300 °C.

Development of Ammonium-Selective Electrode Based on PVC/MB28 Membrane

In this study, the ISE-NH4+ sensor based on hybrid membrane of the poly (vinyl chloride)/methyl methacrylate-butyl acrylate 2:8 co-polymer (PVC/MB28) has been successfully developed, where the ratio between PVC: MB28 is 9:1. Meanwhile, the plasticized material used is dioctyl sebacate (DOS) of 66.34 wt. %, the amount of lipophilic salt of the potassium tetrakis (4-chlorophenyl) borate (KTpClPB) used is 0.99 wt. %, and nonactine as much as 2.97 wt.%. The addition of the MB28 co-polymer has successfully improved the performance and mechanical strength of ISE-NH4+ especially at measurements at 40°C. The ISE-NH4+ sensor based on PVC/MB28 has a Nernstian number of 55.4 and 58.7 mV/dec for measurement at 25°C and 40°C with the linear range between 0.1 - 10−5 M. While the ISE-NH4+ sensors based on PVC used as benchmarking have Nernstian numbers of 54.2 and 35.3 mV/dec for measurements at 25 ° C and 40 ° C, where the linear range is 0.1 - 10−5 M and 0.1 - 10−3 M. The addition of MB28 also does not cause the selectivity of the ISE-NH4+ sensor to decrease, where the result of the selectivity between PVC/MB28 is comparable to PVC.

Flexible, self-standing and patternable P(MMA-BA)/TiO2 photonic crystals with tunable and bright structural colors

To meet the requirement for flexible and transferrable optical equipment in life, developing flexible and self-supported photonic crystals (PCs) is substantially meaningful. Herein, we presented a facile and eco-friendly method to construct flexible, self-standing organic/inorganic hybrid 1DPCs with bright and tunable structural colors. 4-stack nanoparticle-based poly(methyl methacrylate-butyl acrylate) (P(MMA-BA)/TiO2) PCs are fabricated on low-surface-energy polypropylene substrates and covered with polydimethylsiloxane (PDMS) precursor afterwards. Through thermal treatment, the PCs together with cured PDMS can be easily lifted off without other post-treatment, and the color hue of the transferred 1DPC films holds good consistency with that before transfer. Tension test shows the self-standing PC film has good flexibility and better toughness than bare PDMS film. Based on this simple operation, patterned PC films can be achieved as long as placing a mask before covering the precursor. Due to organic vapor sensitivity of P(MMA-BA), this colorful self-supported PC structure shows distinguishable color change when exposing to different vapors, realizing naked-eye recognition of the solvents with the flexible organic/inorganic hybrid 1DPC device.

An environmentally benign methodology to elaborating polymer nanocomposites with tunable properties using core-shell nanoparticles and cellulose nanocrystals

An environmentally benign concept based on waterborne systems is developed for preparation of novel nanocomposite materials with tunable properties. The designed nanocomposites are based on combination of core-shell latex nanoparticles, cellulose nanocrystals (CNC) and polyethylene glycol (PEG). First, core-shell latex nanoparticles from copolymer (methyl methacrylate-ethylene glycol dimethacrylate)-core and copolymer (methyl methacrylate-butyl acrylate)-shell (CS15) are prepared by starved emulsion polymerization. Likewise, incorporation of CNC aqueous suspension into the core-shell latex without any further chemical modification of the nanofiller while assuring good compatibility between both entities is achieved. PEG is effectively added to the suspension to assure multiple functions in the final material. After mixing of the ternary systems, the nanocomposites are prepared by three approaches, i.e. solution casting, solution casting followed by compression molding, and freeze drying followed by compression molding. SEM analysis shows that compression molding processes lead to the highest degree of coalescence of CS15 nanoparticles. This effect is however reduced in presence of PEG or PEG/CNC. It is further observed that the presence of PEG helps protecting CNC from thermal degradation. Thermal and thermo-mechanical analyses prove a high plasticizing performance of PEG and its good confinement between the nanoparticles and at interstitial spaces. Furthermore, it is revealed that the level of material reinforcement by CNC depends strongly on the ratio between CNC and PEG due to the establishment of strong interactions via hydrogen bonding between both components, which can affect the formation of CNC percolating network. These findings allow tuning the microstructure and related properties of the nanocomposites.

Core-shell nanoparticles toughened polylactide with excellent transparency and stiffness-toughness balance

Polylactide has attracted increasing focus on packaging and other consumer products nowadays, due to its stiffness, biodegradability and good transparency. However, its toughened blends are usually utilized to conquer its inherent brittleness, unfortunately, bringing with undesirable opaqueness. Considering the transparency and toughness of PLA, nanoparticles with core-shell structure, which are one kind of methyl methacrylate–butyl acrylate (ACR) copolymers whose rubbery cores resist impact and the glassy shells provide rigidity and compatibility to the polymer matrix, were manipulated by seed emulsion polymerization in this work, aiming to toughen PLA without the substantial decrease of transparency and tensile strength simultaneously. The effects of size and content of ACR nanoparticles on the optical properties, mechanical properties of PLA/ACR blends respectively were clarified. The PLA/ACR blends exhibited excellent transparent property with a transmittance as high as 75% (550 nm). We found an unexpected relationship between particles size and transparency, that is, with the decrease of ACR size, the transparency of blends was also reduced slightly. This phenomenon may contribute to the scattering of bigger aggregation formed by ACR with smaller size, which was identified by microstructure observations. Tensile testing showed the maximum elongation at break of 279.9% when ACR content reached 20 wt%, which was a 65-fold increase compared with neat PLA. Promisingly, the elastic modulus and tensile strength exhibited less decreased with the value of 55.7 MPa and 2.06 GPa respectively, and this blends displayed 8 times the Izod impact strength over neat PLA. It was revealed the shear yielding of matrix and cavitation of particles during the loading process led to the excellent toughness of PLA/ACR blends.

Surfactant-free hybrid latexes from enzymatically hydrolyzed starch and poly(butyl acrylate-methyl methacrylate) for paper coating

The use of starch as renewable resource to produce eco-friendly hybrid latex has received an increasing attention in industrial application. In this work, enzymatically hydrolyzed starch-graft-poly(n-butyl acrylate-co-methyl methacrylate) (ES-g-P(BA-MMA)) latexes were synthesized by seeded surfactant-free emulsion polymerization. A complex initiation system was used to enhance the grafting efficiency. The mechanisms of initiation and graft copolymerization were discussed. The ES-g-P(BA-MMA) latexes were characterized by Fourier transform infrared spectroscopy, dynamic light scattering, transmission electronic microscopy (TEM), and differential scanning calorimetry. The effect of reaction condition on graft copolymerization was investigated. The evolution of particle morphology was revealed by the TEM. The ES-g-P(BA-MMA) latexes were used as binders for paper coating. The strength-related properties of coated paper were evaluated. The results showed that the folding resistance and picking resistance were improved. All the other properties were at least equally good as in the reference sample. The crosslinked ES-g-P(BA-MMA) latex was more effective in improving properties. The folding resistance and wet tensile strength index were enhanced significantly by 29.5% and 36.6%, respectively. This study provides an alternative choice for paper coating to develop coated paper with better properties.

Efficient modification of nanosilica particles in preparation of anti-scratch transparent polyacrylic films through miniemulsion polymerization

Surface modification of silica nanoparticles was performed chemically by using glycidyl methacrylate and the conditions were optimized to reach to a reasonable efficiency. Nanocomposite particles containing the above modified nanosilica were prepared through miniemulsion polymerization in the presence of methyl methacrylate–butyl acrylate–methacrylic acid. Latex particle size and morphology were thoroughly investigated by DLS, SEM, AFM and TEM analyses. Results showed that the silica nanoparticles were well-dispersed in the polymer matrix to induce their properties remarkably. A quantitative EDX analysis was used for indirect assessment of the encapsulation efficiency and the encapsulation efficiency of silica nanoparticles was found 92 %. The obtained nanocomposite films were highly transparent according to the UV–Vis analysis and were able to transmit more than 80 % of visible light. Excellent scratch resistances of the nanocomposite films were obtained in the presence of silica nanoparticles due to the optimum dispersion and their friction coefficients were investigated.

Effects of the addition mode and amount of organic montmorillonite in soft-core/hard-shell emulsion on fire protection, water resistance and stability of fire retardant coating

Abstract In order to meet the basic demands for everyday use and construction requirements, the organic montmorillonite/poly-(Methyl methacrylate-butyl acrylate)/poly-(Methyl methacrylate-butyl acrylate −methacrylic acid) soft-core/hard-shell emulsion was synthesized and used as the film former of the waterborne intumescent fire retardant coating. The effects of addition mode and amount of organic montmorillonite in emulsion on coating properties were studied. Emulsion stability analysis, water resistance tests of films and fire resistance tests all showed the optimum addition mode of OMMT was in the core layer of soft-core/hard-shell emulsion. The reason could be that the addition of OMMT in core layer could not destroy core-shell structure and cross-linked structure, and parallel-arranged OMMT was distributed well. The result of differential scanning calorimetry (DSC) showed that soft-core/hard-shell emulsion containing OMMT in core layer had lower glass transition temperature (Tg) of core layer and higher glass transition temperature (Tg) of shell layer, which play an important role in lowering film-forming temperature and enhancing resistance to water. The results of fire protection test indicated the fire resistance of coatings were significantly improved by adding OMMT in the range of 1.0 wt.% to 1.5 wt.% in core layer and scanning electron microscopy (SEM) demonstrated that the well-dispersed OMMT could improve the foam structure of char layer by limiting the escape of inert gases and filling carbon layer’s tiny cracks generated at high temperature.

The Influence of Epoxy Functionalized Acrylate Particles on the Properties of Plasticized PLA Blown Films

Polylactide (PLA) was plasticized with poly(diethylene glycol adipate) (PDEGA). The plasticized PLA was further blended with core-shell structured particles of glycidyl methacrylate-functionalized methyl methacrylate-butyl acrylate copolymer (GACR) using a twin-screw extruder, and the extruded samples were blown using the blown thin film technique. Both PDEGA and GACR significantly influenced the physical properties of the films. Compared to neat PLA, the elongation at break and tear strength of the films were significantly improved. The shear yielding induced by cavitation of GACR particles was the major tearing mechanism. GACR could act as a tear resistance modifier for PLA blown films. The spherulite size of the PLA/PDEGA/GACR films decreased with the addition of GACR. The biodegradability of the PLA/PDEGA/GACR films decreased slightly. These findings contributed new knowledge to the additive area and gave important implications for designing and manufacturing polymer packaging materials.

Synthesis and properties of SiO2/P(MMA-BA) core–shell structural latex with siloxanes

Abstract In this study, we have successfully introduced siloxane monomer, 2,4,6,8-Tetravinyl-2,4,6,8-tetramethylcyclotetrasiloxane (V4) into the shell of silica/poly(methyl methacrylate-butyl acrylate) (SiO2/P(MMA-BA)) core–shell nanocomposite colloids via in-situ emulsion copolymerization. The obtained nanocomposite films with 50% silica content all show excellent transparency (nearly 100% transmittance in visible range) and film-forming property (Tg under 30 °C). More importantly, the addition of V4 can significantly increase the weathering durability of the film by improving the water repellency, cross-linking degree and UV-blocking property of the film.