Preparation And Application Of Straw-fiber/Red Clay/pp Foaming Ternary Composites

Noise is a resource of pollution that do harm to environment as atmospheric pollution and water pollution. it is severely harm to the human auditory system, even danger the cardiovascular and fertility, in some instance, it also endanger the safety of the country. Therefore the noise control and study is not only for the environment protection requirement but also for the need of keeping the safety of the country.The paper aimed at the study of preparation and properties PP foamed polymer composite filled with straw. The PP matrix was filled with straw, which has 60,100, or 200 meshes. Three kinds of modifications including microwave radiation grafting, titanate coupling and silane coupling processing were carried out to improve interface compatibility between straw and PP, with a bit of adamic earth to enhance capability of foaming and nucleating, azodiearbonamid (AC) as blowing agent, ZnO as blowing promoter, straw fibers, PP as well as a variety of additives. All the materials mixed well on compression molding machine fully by keeping the process at the right temperature and time strictly, and then foaming to mold on the flat vulcanizing machine, which the adamic earth/straw/PP multifunctional, acoustic absorbed, foamed composite was achieved. Finally, run the test of the samples on different properties and analyze section morphology of the composite.1. Through the observation of micro-structure of NFRP by SEM,untreated sawdust has a smooth surface while the one treated by microwave and coupling agent forms a uniform pore structure and roughness of surface becomes larger.The SEM results revealed that the surface of straw fibers by micro-wave radiation changed and the ultrastucture also became complex.2. Moreover, the analysis of the density and water absorption show:the water absorption of the composites was raised with the addition of azodicarbonamide(AC) and the density was reduced first and then raised. Similarly, when the straw content increased from 0 parts to 50 parts, the water absorption of the composites was raised and the density was reduced first and then raised. Compared with untreated straw-polymer composite, the water absorption of the treated one was reduced.3. The analysis of the sound absorption coefficient shows that as the addition of azodicarbonamide(AC) increased from 1part to 5 parts the straw-polymer composite got good absorbent properties within the range of high frequency. Comparatively, when the straw contents increased from 0 to 50 parts, sound absorption coefficient has been raised within the range of low frequency and medium-high frequency.Besides, compared with untreated straw-polymer composite the treated one by titanate coupling agent has a raised sound absorption coefficient from 0.35 to 0.55. when the red clay increased from 0 to 5 parts, sound absorption coefficient is not obvious within the range of low- medium frequency, However, it has been raised within the range of medium-high frequency. When the red clay added 3 parts, the sound absorption coefficient has been raised from 0.35 to 0.61. Compared with untreated red clay-polymer composite, the sound absorption coefficient is unchanged.4. The specific tensile strength of the straw-polymer composites were decreased all the time while addition of straw from 0 to 50 parts.On the opposite,when the red clay contents increased from 0 to 5 parts, we could find the specific tensile strength has been raised. Furthermore, the treatment of coupling agent, especially the titanate coupling agent,could raise the straw-polymer composites'tensile strength.According to the results given above, we could know that the density of the straw-polymer composite will decrease by adding more straw fiber and the sound -absorbing ability within the range of medium-high frequency will rise. Besides, by treatment of coupling agent or microwave radiation to the straw fiber, we could raise the straw fiber composite's sound-absorbing ability and tensile strength.Furthermore, suitable addition of red clay can raise the composite's sounding absorbing ability and tensile strength.