Blends of poly(phenylene sulfide) (PPS) and recycled poly(ether ether ketone) (r-PEEK) were prepared using a twin-screw extruder. The carbon nanotube (CNT) added to the blends not only improved the compatibility of the two polymers, but also affected the morphology of the immiscible PPS/r-PEEK blends. R-PEEK always forms the dispersed phase and PPS the continuous phase in such blends. In the composite, CNT particles were observed in the PPS phase, mostly distributes in the interface between PPS and PEEK. The results show that r-PEEK improves the impact and tensile strength of PPS, but does not provide nucleation effect on PPS. However, CNT improved the flexural modulus of PPS/r-PEEK blends and promoted the crystallization of r-PEEK rather than that of PPS. The prepared PPS/r-PEEK blends provided larger electrical conductivity than neat polymers. Adding 20 wt % CNT to blend resulted in composite with the minimum volume resistivity, a reduction of four orders of magnitude, compared with that of the neat blend. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42497.

In this article, a novel eggshell/β-PP bio-composite was prepared and evaluated. First the waste chicken eggshell (ES) was modified by a stingy amount of pimelic acid (PA) through solution method, and then compounded with PP through melt blending method. The crystalline form, mechanical properties, and morphology of the ES/β-PP composites were studied. The results showed that ES modified by PA was a β nucleating agent with high efficiency and selectivity, resulting in the maximum K_β value of 0.99 in PP composites. PA modification promoted the dispersion and interfacial bonding of ES in PP. Although the addition of PA-modified ES slightly decreased tensile properties and flexural properties of PP, it increased the impact strength of PP by 228% than that of pure PP. Taking all factors into consideration, the optimal mass ratio of PP/ES/PA composites for reaching optimum mechanical properties should be 100/5/0.000471. Thus, the application of modified ES to prepare ES/β-PP bio-composites represents a promising way to mitigate environmental pollution and to reduce the cost of polyolefin products. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

β-Nucleated polypropylene (PP), uncompatibilized β-nucleated PP/poly(trimethylene terephthalate) (PTT), β-nucleated PP/PTT blends compatibilized with maleic anhydride (MA)-grafted PP (PP-g-MA), and styrene–ethylene–propylene copolymer were prepared with a twin-screw extruder. The morphology, compatibility, crystallization characteristic, melting behavior, and crystallization kinetics were investigated. The result shows that β-nucleated PP was incompatible with PTT, and the addition of the two compatibilizers decreased the interfacial tension between β-nucleated PP and PTT; this led to improved dispersion and strengthened interfacial bonding in the blends. PP-g-MA had a better compatibilization effect. All of the researched β-nucleated PP/PTT blends contained β crystals of PP, and the compatibilizers exhibited synergistic effects with the β-nucleating agent to further increase the content of β crystals. Nonisothermal kinetic analysis indicated that Mo's method described the nonisothermal crystallization behavior of the β-nucleated PP/PTT blends satisfactorily, and the Avrami approach could only describe the early stage of the crystallization appropriately, whereas the Ozawa method failed to have the same effect. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

This article deals with the feasibility of using recycled corrugated paper board (rPF) as the reinforcing material for recycled plastics. The composites of recycled polypropylene (rPP) and rPF were prepared by extrusion compounding and injection molding, and the rPP/rPF composites compatibilized by maleic anhydride grafted PP (PP-g-MA), maleic anhydride grafted ethylene-1-octene copolymer (POE-g-MA), and maleic anhydride grafted styrene-ethylene-butylene-styrene copolymer (SEBS-g-MA) were also prepared. The crystallization and melting behavior, mechanical properties, thermal stability, and morphology of these composites were studied. The results indicated that rPF promoted the crystallization, enhanced the strength and toughness of rPP/rPF composites to some extent while decreased thermal stability at the same time. PP-g-MA and POE-g-MA improved the dispersion and interface adhesion of rPF, and further upgraded the mechanical properties and vicat softening temperatures. Among these compatibilizers, PP-g-MA was most favorable to the strength improvement while POE-g-MA was most favorable to the toughness improvement. As for SEBS-g-MA, it had no obvious modification effect. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

Polypropylene (PP)/wasted poly(ethylene terephthalate) (PET) fabric composites and these composites modified by maleic anhydride grafted polypropylene (PP-g-MA) and reactive monomers were prepared with a twin-screw extruder. The crystallization morphology, nonisothermal crystallization and melting behavior, crystallization kinetics, and isothermal crystallization kinetics were investigated with differential scanning calorimetry. The results indicated that the wasted fabric (WF) had a heterogeneous nucleation effect on PP in the composites, and this increased the crystallization temperature and induced PP to form transcrystallinity. PP-g-MA further increased the crystallization temperature; however, the reactive monomers weakened the heterogeneous nucleation effect of WF. Also, the premelting temperature affected the crystallization and melting behavior of the composites significantly. The Avrami equation and the Mo method provided a fairly satisfactory description of the crystallization kinetics. The crystallization activation energy, nucleation constant, and folding surface free energy of PP were markedly reduced in the PP/waste PET fabric composites and the compatibilized composites. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci 00: 000–000, 2011