Expanding the applications of poly(butylene succinate) (PBS) in processing fields requiring high melt strength, PBS/solid epoxy (SE)/carboxyl-ended polyester (CP) blends with high melt viscosity were fabricated by the in-situ crosslinking reaction using SE and CP. The influence of SE/CP had been studied in terms of the rheological property, crystallization behavior, and mechanical property of PBS. The results showed that the melt viscosity of PBS could be enhanced significantly by three orders of magnitude, when the loading ratio of SE to CP was over 15/15. Furthermore, it had also been found that SE/CP component had positive impact on the mechanical properties of PBS, inclusive of reduction of brittleness. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42193.

To improve the thermal and mechanical properties and further to expand its applications of epoxy in electronic packaging, reduced graphene oxide/epoxy composites have been successfully prepared, in which dopamine (DA) was used as reducing agent and modifier for graphene oxide (GO) to avoid the environmentally harmful reducing agents and address the problem of aggregation of graphene in composites. Further studies revealed that DA could effectively eliminate the labile oxygen functionality of GO and generate polydopamine functionalized graphene oxide (PDA-GO) because DA would be oxidated and undergo the rearrangement and intermolecular cross-linking reaction to produce polydopamine (PDA), which would improve the interfacial adhesion between GO and epoxy, and further be beneficial for the homogenous dispersion of GO in epoxy matrix. The effect of PDA-GO on the thermal and mechanical properties of PDA-GO/epoxy composites was also investigated, and the incorporation of PDA-GO could increase the thermal conductivity, storage modulus, glass transition (T_g), and dielectric constant of epoxy. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39754.

To reduce environmental pollution and oil shortages, biodegradable polylactide (PLA) from plants was used to replace synthetic plastic from petroleum. In this study, high-melt-viscosity PLA was achieved through the in situ reaction of carboxyl-ended polyester (CP) and solid epoxy (SE) first; then, PLA foams were successfully prepared by a chemical compression-molding method. The detailed foaming factors were also studied, including the decomposition temperature of the blowing agent, the foam temperature, and the open-mold temperature. The results reveal that the obtained PLA foams had good water absorption and degradable properties, and the foam density was low as 0.16 g/cm³. Moreover, the effects of the CP/SE concentration and the AC content on the properties of the foams were also investigated. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

To extend the applications of wood–plastic composites (WPCs), soft WPCs were prepared with ethylene vinyl acetate (EVA) and wood flour (WF) as major components via a two-step process involving two-roll mixing and compression molding. The effect of the various factors, such as WF, unsaturated fatty acid (UFA), and dicumyl peroxide contents, on the mechanical properties, processability, and morphology of the WPCs was investigated in detail. The addition of UFA could effectively improve the processability and flexibility of the composites. The in situ grafting reaction between UFA and EVA considerably improved the adhesion of the WF and resin matrix. Consequently, soft WPCs with good performances in flexibility and processability were successfully obtained. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Polystyrene (PS)–γ-methacryloxypropyl trimethoxy silane (MPTMS) copolymer/zirconia (ZrO₂) nanohybrid materials were successfully prepared by the combination of solvothermal and in situ synthesis methods, in which the comonomer was used as chemical bonding agent between the nanoparticles and the matrix, and acetylacetone (AcAc) was used as a size control agent of ZrO₂ in the PS matrix. Then, a new transparency film with a relatively high refractive index (1.72) was successfully obtained, in which ZrO₂ could be dispersed well in the PS–MPTMS matrix. Field emission scanning electron microscopy images indicated that AcAc was helpful in the dispersion of the nanoparticles, and smaller ZrO₂ particles with no aggregation were obtained in the PS–MPTMS matrix. The structure and thermal properties of the hybrid films were investigated by Fourier transform infrared spectroscopy and thermogravimetric analysis, and the surface properties were also examined. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2320–2327, 2013

To produce biodegradable poly(butylene succinate) (PBS) foam by compression molding, high viscosity PBS was prepared with dicumyl peroxide (DCP) as a crosslinking agent and trimethylolpropane trimethacrylate (TMPTMA) as a curing coagent by crosslink method. The influences of various factors on the foaming process and the properties of PBS foams were investigated. The results show that the use of DCP and TMPTMA simultaneously can effectively increase the melt viscosity of PBS. Zinc oxide/zinc stearate was used to reduce the thermal decomposition temperature of the blowing agent azodicarbonamide, which can balance well the vulcanization of PBS and the decomposition of blowing agent. Finally, closed-cell PBS foams with degradable property have been successfully prepared by a traditional chemical compression molding foaming way. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

To extend the potential applications of polylactide (PLA) in film blowing, foaming, thermal molding, and so on, the high-viscosity PLA composites with various compositions of carboxyl-ended polyester (CP) and solid epoxy (SE) have been successfully prepared by an in situ reaction blending process. Their rheological properties, crystallization behaviors, tensile properties, and morphologies have been investigated in detail. The results show that the complex viscosity η*, G′, and G″ at low-frequency region and the tensile strength of PLA composites are obviously improved with the addition of CP/SE, but the nonisothermal crystallization of PLA component is hindered. SEM reveals that some microphase separations existed in the as-prepared composites. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

A solvothermal process was developed to in situ prepare epoxy (EP)/TiO₂ hybrid precursors. The chemical structure of samples was confirmed by X-ray and Fourier transformed infrared spectroscopy. Field emission scanning electron microscope micrographs of cured EP/TiO₂ hybrid composites showed that well-dispersed TiO₂ nanoparticles were successfully in situ formed in epoxy matrix through the solvothermal process. The thermogravimetic analysis, DSC, and gel content measurements showed that EP/TiO₂ hybrid precursors were fully cured with the glass transition temperature decreasing gradually. The effect of TiO₂ contents on optical and surface properties was investigated in detail. The results indicated that epoxy/TiO₂ nanocomposites exhibited excellent UV shielding effect and high visible light transparency. The contact angle of EP/TiO₂ nanocomposites, when the content of silane-coupling agent (KH560) was 5 g and the content of tetrabutyl titanate (TBT) was 3 g, can reach as high as 101°, which was 36° higher than that of pure EP, representing for the increase of hydrophobicity. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Homogenous poly(lactic acid) (PLA)/zinc sulfide (ZnS) nanocomposites were successfully prepared via a solvothermal method with lactide, zinc acetate, and carbon disulfide as precursors. In this process, the cationic ring-opening polymerization of lactide and the formation of ZnS nanoparticles were taken place simultaneously, and PLA/ZnS nanocomposites were obtained in situ way. The effect of reaction temperature, time, and zinc acetate content on the molecular weight of PLA was discussed. Ubbelohde viscometer, TEM, UV–vis, TGA, and fluorophotometer were used to characterize the obtained nanocomposites. It was found that homogonous PLA/ZnS nanocomposites could be obtained at 160°C for 8 h with toluene as reaction medium. Comparing to pure PLA, the molecular weight of PLA in the obtained nanocomposites increased, and ZnS nanoparticles with the size about 10 nm in diameter were dispersed well in PLA matrix without any dispersan. The PLA/ZnS nanocomposites have ultraviolet resistant. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Composites of high density polyethylene (HDPE) with the reinforcements of glass fiber (GF) and wood flour (WF) have been studied in this work. High-density polyethylene-grafted maleic hydride (HDPE-g-MAH) was used as a compatibilizer. In particular, the effect of GF, WF, and HDPE-g-MAH on the overall properties of GF/WF/HDPE composites (GWPCs in short form) was systematically studied. The results indicate that HDPE-g-MAH as a compatibilizer can effectively promote the interfacial adhesion between GF/WF and HDPE. By the incorporations of GF/WF, the heat deflection temperature can reach above 120°C, and the water absorption can be below 0.7%, also the tensile strength, flexural strength, and impact strength of GWPCs can surpass 55.2 Mpa, 69.4 Mpa, and 11.1 KJ/m², respectively. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

A novel processing method of combining dynamic vulcanization with the silane-grafted water-crosslinking technique to improve the comprehensive properties of polyethylene (PE) is reported. PE was grafted with vinyl triethoxysilane (VTEO) first, and then, N,N,N′,N′- tetragylcidyl-4,4′-diaminodiphenylmethane epoxy resin was dynamically cured in a PE-g-VTEO matrix through a twin-screw extruder to prepare PE-g-VTEO/epoxy blends. Polyethylene-graft-maleic anhydride (PE-g-MAH) was used as a compatibilizer to improve the interaction between PE-g-VTEO and the epoxy resin. The results show that the novel processing method improved the strength, stiffness, and toughness of the blends, especially the heat resistance of the blends, by the addition of the dynamically cured epoxy resin as the reinforcement. PE-g-MAH increased the compatibility between PE-g-VTEO and the epoxy resin, which played an important role in the improvement of the comprehensive properties of the blends. In addition, after treatments in both hot air and hot water, the comprehensive properties of blends were further improved, thanks to the further curing reaction of epoxy with PE-g-VTEO. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

The copolymer of styrene–ethylene–butylene–styrene triblock copolymer-g-polylactic acid (SEBS-g-PLA) was successfully prepared using a novel solvothermal synthetic method, in which the graft copolymerization of PLA and SEBS was simply performed in cholorform solution at 100–150°C with benzoyl peroxide (BPO) as initiator. The effect of various factors including the reaction temperature and time and the content of BPO and PLA on the graft copolymerization was investigated in detail. It is found that the optimal reaction condition for the grafted copolymers SEBS-g-PLA was 120°C for 5 h, while the optimal formulation of SEBS/PLA/BPO was 5 g/2 g/0.5 g in 30 mL chloroform. The properties and microstructures of the obtained SEBS-g-PLA copolymers were also studied. The tensile strength and elongation at break were higher than that of pure SEBS and improved with the increase of grafting degree. In addition, SEBS-g-PLA copolymer possessed two-phase structure with vague phase boundaries. The as-prepared SEBS-g-PLA copolymers can be used as the toughening component to improve the impact strength of PLA. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

Polystyrene (PS)/montmorillonite nanocomposites were prepared by the free-radical polymerization of styrene-containing dispersed clay in a direct current electric field. The intercalation spacing in the nanocomposites, the dispersion, and the orientation of these composites were investigated. The nanocomposites had higher T_g and better thermal stability when compared with the virgin PS. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Solvothermal process was successfully developed to graft dibutylmaleate (DBM) onto poly(ethylene-co-1-octene) (POE) with dicumyl peroxide (DCP) as free radical-initiator. FTIR spectra demonstrate that DBM is successfully grafted onto the backbone of POE by this novel method. The influences of DBM content, DCP concentration, POE concentration, reaction temperature and reaction time on the grafting copolymerization have been investigated in detail through grafting degree (GD). It is worthy to indicate that high grafting degree (above 15%) can be achieved through the one-pot way when the graft reaction is carried out in 40 mL toluene at 150°C for 5 h with 1.6 g DBM, 6–8 g POE and 0.35 g DCP. This developed solvothermal process is becoming an effective way to prepare POE-g-DBM graft copolymers, and can be extended to other systems. In addition, TGA results show that the thermal properties of POE are enhanced after the grafting reaction. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

The free-radical graft copolymerization of maleic anhydride (MAH) onto highly reactive low molecular weight polyisobutylene was conducted by the use of benzoyl peroxide as an initiator through the solvothermal method. Fourier transform infrared spectra and ¹H-NMR spectra confirmed that maleic anhydride was successfully grafted onto highly reactive low molecular weight polyisobutylene backbone, and the grafting mechanism also was proposed. The effect of benzoyl peroxide content, MAH concentration, total reactant amount in the reaction vessels, reaction temperature and time, and different kinds and volumes of solvents on MAH's degree of grafting was investigated in detail. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

High-density polyethylene/wood flour (HDPE/WF) composites were prepared by a twin-screw extruder. The effects of WF, silane coupling agents, polymer compatibilizers, and their content on the comprehensive properties of the WF/HDPE composites have been studied in detail, including the mechanical, thermal, and rheological properties and microstructure. The results showed that both silane coupling agents and polymer compatibilizers could improve the interfacial adhesion between WF and HDPE, and further improve the properties of WF/HDPE composites, especially with AX8900 as a compatibilizer giving higher impact strength, and with HDPE-g-MAH as a compatibilizer giving the best tensile and flexural properties. The resultant composite has higher strength (tensile strength = 51.03 MPa) and better heat deflection temperature (63.1°C). © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

The technique of grafting silane by in-situ extrusion to improve the compatibility between wood flour and high density polyethylene (HDPE) composites was studied. It was found that the silane grafted composites showed enhanced mechanical properties compared to both the coupled and non-coupled PE-g-MAH composites. The effects of silane contents and dicumyl peroxide (DCP) concentrations on the mechanical properties of the composites were investigated in detail. Moreover, the water absorption, morphology and thermal stability of the composites were also investigated. Copyright © 2008 John Wiley & Sons, Ltd.

The poly(ethylene 1-octene)-g-maleic anhydride copolymers (POE-g-MAH) with high grafting degree (GD) (>9%) have previously been obtained by a solvothermal method in our laboratory. It is found that the low GD (less than 2.5%) did not change the bulk properties of polyolefine elastomers (POE). Thereforefore, it is worth further understanding whether a high GD POE-g-MAH copolymer differs from the pure POE in its comprehensive properties and performance. In this article, POE-g-MAH with different GDs were synthesized and characterized by thermogravimetric analyze (TGA), differential scanning calorimetry (DSC), wide angle X-ray diffraction spectroscopy (WAXD), and dynamic rheological testing. The results show that the thermal decomposition temperature, melting points, the crystallization temperatures, and the crystallinities were decreased by the increasing GD. By WAXD, three peaks respectively, attributed to the amorphous phase, the (110) and (200) interferences of the orthorhombic unit cell were detected, and they also decreased by the increasing GD. And the POE-g-MAH copolymers had higher storage modulus (G′), loss modulus (G″), and complex viscosity (η*) than those of pure POE. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

The grafting of a polymer can lead to the improvement and modification of the polymer and thus expand its applications. Grafting methods include solution grafting in organic solvents, melt grafting at high temperatures, and light grafting with radioactive sources. These methods have their advantages and disadvantages. The disadvantages include waste treatment, consumption of energy, and so on. In this study, a hydrothermal process which is called the green approach, was developed to prepare graft copolymers. The effect of various factors on the grafting degree was investigated in detail. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

To produce polyethylene–octene elastomer foams with compression molding, the influences of various activators on the thermal decomposition temperature of the chemical blowing agent azodicarbonamide were investigated with thermogravimetric analysis, which showed that the decomposition temperature of azodicarbonamide could be effectively reduced by the addition of zinc oxide/zinc stearate. The results of a moving die rheometer suggested that the vulcanization and blowing curves were influenced by the content of azodicarbonamide and temperature, and the optimum temperature was about 170°C. The morphology and physical properties of the microcellular polyethylene–octene elastomer were studied. The results indicated that the amount of azodicarbonamide and the processing temperature played important roles in the cell morphology and physical properties of polyethylene–octene elastomer foams. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci 2008