Effects of Modification on Structure and Properties of Ramie Fiber/Polypropylene Composites

Ramie fiber and polypropylene were used as raw materials, ramie fiber/polypropylene composites were prepared by compression molding process,the effects of treating the ramie fiber with silane coupling agent and compatibilizing the composite with maleic anhydride gafted polypropylene(MAPP) on the structure, melting and mechanical properties of the composites were studied, the effects of immersion time in water on the mechanical properties of the composites were also investigated. The results show that,both the modification with coupling agent and by means of compatibilizing agent can strengthen the interfacial bonding between the fiber and matrix in the composite,and also improve its thermal stability. All the modified composites have greater strengths and moduli than the unmodified ones when immersed in water for any periods,especially the impact strength of the MAPP compatibilized composite not only increases with immersion time in water dramatically,but also is improved from that of the unmodified one by 104.84%,239.40%,294.48% and 320.01% respectively when immersed in water for 0,7,14 and 21d.