Natural Fiber Reinforced Poly(vinyl chloride) Composites: Effect of Fiber Type and Impact Modifier

Poly(vinyl chloride) (PVC) and natural fiber composites were prepared by melt compounding and compression molding. The influence of fiber type (i.e., bagasse, rice straw, rice husk, and pine fiber) and loading level of styrene-ethylene-butylene-styrene (SEBS) block copolymer on composite properties was investigated. Mechanical analysis showed that storage modulus and tensile strength increased with fiber loading at the 30% level for all composites, but there was little difference in both properties among the composites from various fiber types. The use of SEBS decreased storage moduli, but enhanced tensile strength of the composites. The addition of fiber impaired impact strength of the composites, and the use of SEBS led to little change of the property for most of the composites. The addition of fiber to PVC matrix increased glass transition temperature (T_g), but lowered degradation temperature (T_d) and thermal activation energy (E_a). After being immersed in water for four weeks, PVC/rice husk composites presented relatively smaller water absorption (WA) and thickness swelling (TS) rate compared with other composites. The results of the study demonstrate that PVC composites filled with agricultural fibers had properties comparable with those of PVC/wood composite.     

Hydro-erosive separation of plastic fibers from textile compounds

There are no known methods which will effectively separate compounds consisting of plastic fibers and latex binders, or plastics coated with textiles. To separate the fibers and the plastic carrier from the other materials, high-pressure water jets have been used. Based on this practice, a method was developed to treat waste carpets and automotive interior materials with water jets in order to recycle their plastic components. Experiments were performed to investigate the modes of destruction as well as the influence of process parameters. Based on these investigations, a pilot device for the treatment of waste carpets (sheets or chips) was designed and installed. It was shown that the proposed method works with a high degree of cleanliness and selectivity. A general process scheme was developed in order to apply the method to recycling processes.