This study investigated the morphology, tensile properties, thermal conductivity, and thermal stability of short carbon fiber reinforced polypropylene (CF/PP) composites. CF/PP composites were prepared with varying amounts of short carbon fiber (9,15,20, 25, and 30 wt%) in PP matrix with and without maleic anhydride grafting PP as a coupling agent. Samples were prepared by extrusion blending followed by injection molding. Results showed that the addition of CFs significantly improved the tensile modulus and tensile strength of composites by 455% and 168%, respectively, at 30 wt% loading compared with pure PP. Thermogravimetric analysis results indicated that increasing the CF content improved the thermal stability of composites compared with PP. In addition, thermal conductivity increased with increasing CF weight fraction. The microstructural analysis results showed that maleic anhydride grafting PP improved the adhesion between carbon fibers and PP matrix. POLYM.

Effects of the addition of short carbon fibers (CFs) on the mechanical, physical, and morphological properties of polypropylene (PP) and woodpolypropylene composites (WPCs) were investigated. Hybrid composites (mix of wood and CFs) were manufactured in a two-stage process, pellet extrusion and samples mold injection with varying amounts of poplar wood fiber (0%, 20%, 30%, and 40%) and CFs (0%, 3%, 6%, and 9%), with and without maleic anhydride grafted PP (MAPP) as a coupling agent. The composites were prepared with extrusion blending followed by injection molding. The samples where then tested for mechanical and physical properties, and fractured surfaces where observed with scanning electron microscopy. The results indicated that the addition of CFs to WPCs improved the tensile and flexural strength and the modulus of elasticity but had only a small influence on elongation at break and impact strength. The density of hybrid composites slightly increased with CFs proportion but their water absorption was not affected. Scanning electron micrographs of the tensile fractured specimens showed improved adhesion of CFs and poplar with the PP matrix in the presence of a coupling agent.

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Die Dithiosäuren (I) reagieren mit Alkenen, wie z.B. (II), in Gegenwart von 2,2.′‐Azo‐bis‐isobuttersäurenitril (AIBN) zu den Dithio1anen(III) (Bildungsmechanismus, NMR‐Spektren).

Thioamide groups were introduced into polystyrenes by the Friedel–Crafts reaction, with phenyl isothiocyanate in nitromethane solution, in the presence of anhydrous aluminium chloride. Free radical copolymerization of 4‐vinyl dithiobenzoate with styrene followed by low‐temperature solution condensation reactions, with excess of amines in N,N‐dimethylformamide, offered another synthetic route to (co)polymers containing thioamine groups in the side chains without crosslinking. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 117–127, 1998