Multi-monomer grafted copolymers, high-density polyethylene-grafted-maleic anhydride-styrene (HDPE-g-(MAH-St)) and polyethylene wax-grafted- maleic anhydride ((PE wax)-g-MAH), were synthesized and applied to prepare high-performance high-density polyethylene (HDPE)/wood flour (WF) composites. Interfacial synergistic compatibilization was studied via the coordinated blending of high-density polyethylene-grafted-maleic anhydride (MPE-St) and polyethylene wax-grafted- maleic anhydride (MPW) in the high-density polyethylene (HDPE)/wood flour (WF) composites. Scanning electron microscopy (SEM) morphology and three-dimensional WF sketch presented that strong interactive interface between HDPE and WF, formed by MPE-St with high graft degree of maleic anhydride (MAH) together with the permeating effect of MPW with a low molecular weight. Experimental results demonstrated that HDPE/WF composites compatibilized by MPE-St/MPW compounds showed significant improvement in mechanical properties, rheological properties, and water resistance than those compatibilized by MPE, MPE-St or MPW separately and the uncompatibilized composites. The mass ratio of MPE-St/MPW for optimizing the HDPE/WF composites was 5:1. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 42958.

Binary and ternary blends composed of poly(lactic acid) (PLA), starch, and poly(ethylene glycols) (PEGs) with different molecular weights (weight-average molecular weights = 300, 2000, 4000, 6000, and 10, 000 g/mol) were prepared, and the plasticizing effect and miscibility of PEGs in poly(lactic acid)/starch (PTPS) or PLA were intensively studied. The results indicate that the PEGs were effective plasticizers for the PTPS blends. The small-molecule plasticizers of PEG300 (i.e., the M_w of PEG was 300g/mol) and glycerol presented better plasticizing effects, whereas its migration and limited miscibility resulted in significant decreases in the water resistance and elongation at break. PEG2000, with a moderate molecular weight, was partially miscible in sample PTPS3; this led to better performance in water resistance and mechanical properties. For higher molecular weight PEG, its plasticization for both starch and PLA was depressed, and visible phase separation also occurred, especially for PTPS6. It was also found that the presence of PEG significantly decreased the glass-transition temperature and accelerated the crystallization of the PLA matrix, depending on the PEG molecular weight and concentration. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41808.

Reactive high vinyl silicone oil (HVSO) was selected to prepare the ceramic silicone rubber composites. The effects of HVSO on the mechanical properties and thermal stabilities of ceramic silicone rubber composites were investigated. The structures of the cross-linked network of silicone rubber with or without HVSO were studied. The intermolecular space of silicone rubber was enlarged, and the cross-linked point was concentrated by addition of HVSO, which was demonstrated by cross-linking densities, scanning electron microscope (SEM) images, and dynamic mechanical analysis (DMA). The cross-linked network model was formed with the slipping of the cross-linked points along with the silicone rubber chain. Mechanical properties of composites were enhanced by the formation of this cross-linked network. The tear strength, tensile strength, and elongation at break of the composites were increased by 18.5%, 13.2%, and 37.4% by the adding of 2 phr HVSO, respectively. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41864.

Novel multifunctional hybrid vinylized epoxide oligomers (MVEOs) containing two different reactive groups were synthesized through the esterification of tetraglycidyl 4,4′-diaminodiphenylmethane (TGDDM) with acrylic acid (AA) at various molar ratios. The changes of vinyl ester and epoxy groups in MVEOs were studied by Fourier Transform Infrared Spectroscopy, Nuclear Magnetic Resonance, and Gel permeation chromatograph. It was found that more amount of AA in the reactant would increase the contents of vinyl ester and molecular weight. The curing behavior of MVEOs has been studied by scanning differential scanning calorimetry (DSC). Two distinct exothermic peaks were observed in the MVEOs which can be attributed to the radical polymerization of vinyl ester/styrene and condensation polymerization of epoxy/MeTHPA, respectively. Two different kinds of curing programs have influenced each other which makes the exothermic peaks overlapped. The DSC scan of MVEO-2 indicated that the radical initiated curing reaction of vinyl ester won't notably affect the curing of epoxy without MeTHPA. However, the thermal curing of vinyl ester in MVEO-2 without MEKP/Co would be occurred with the temperature rising. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42276.

This study focuses on comprehensively investigating polyethylene glycol (PEG) with different molecular weight. Thermal properties of the PEGs were investigated by differential scanning calorimetry (DSC), as well as gradual melting and freezing tests with thermocouples. Results show that the degree of PEG crystallization increased with the increasing of the molecular weight of polymers. The temperatures of pure PEG 1000 and PEG 1000-PEG 600 blends ranged from 20 to 50°C. The apparent activation energy of pure PEG1000 was 300 kJ/mol, whereas that of the PEG blend was 239 kJ/mol. During the crystallization process, Avrami index n ranged from 5 to 3 and half-crystallization time t_1/2 decreased with the acceleration of the crystallization rate R. This difference was due to the increase in polydispersity of the PEG system and decrease in the degree of crystallization. POLYM. ENG. SCI., 54:2872–2876, 2014. © 2014 Society of Plastics Engineers

Recycled poly(ethylene terephthalate)/bisphenol-A polycarbonate/PTW (ethylene, butylacrylate (BA), and glycidylmethacrylate (E/nBA/GMA) terpolymer) were blended in different sequence through low temperature solid state extrusion (LTSSE) was studied. R-PET/PC blends were toughened by PTW, resulting in the improvement of impact strengths. In tensile test, the (PC/PTW)/r-PET blends made by mixing r-PET with the preblend of PC/PTW had noticeable strengthening effect on its tensile properties, which was not impaired by the rubber content due to its strain-hardening occurred following its necking at the constant load. Morphological study by scanning electron microscopy (SEM) was in conformity with the mechanical result. For the (PC/PTW)/r-PET blends, the PC particles were well embedded in the PET matrix and the smooth morphology exhibited. The DSC thermographs for heating and cooling run indicated that the crystallinity of PET rich phase was affected by different blending sequence. In the FTIR test, the different absorption intensity of PC aromatic carbonate carbonyl band was clearly illustrated. The results indicated different blending sequence led to different blending effect. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

Properties of recycled Poly(ethylene terephthalate) were greatly improved. Recycled PET was blended with LLDPE-g-MA by low-temperature solid-state extrusion. Mechanical properties of the blends were affected obviously by the added LLDPE-g-MA. Elongation at break reaches 352.8% when the blend contains 10 wt % LLDPE-g-MA. Crystallization behavior of PET phase was affected by LLDPE-g-MA content. Crystallinity of PET decreased with the increase of LLDPE-g-MA content. FTIR testified that maleic anhydride group in LLDPE-g-MA reacted with the end hydroxyl groups of PET and PET-co-LLDPE-g-MA copolymers were in situ synthesized. SEM micrographs display that LLDPE-g-MA phase and PET phase are incompatible and the compatibility of the blends can be improved by the forming of PET-co-LLDPE-g-MA copolymer. LLDPE-g-MA content was less, the LLDPE-g-MA phase dispersed in PET matrix fine. With the increase of LLDPE-g-MA content, the morphology of dispersed LLDPE-g-MA phase changed from spherule to cigar bar, then to irregular spherule. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008