Study On Structure And Performance Of PP/Tale Composites

This paper made the β nucleating agent of rare earth and ionomer of PP-grafted-Malayacid zinc(PP-g-MAZn) as the modifier respectively to improve the properties ofPolypropylene(PP)/Tale composite by controling the content and grafting rate.The impacts ofstucture and property of mechanics,processing and heat-proof of PP/Tale composite by βnucleator and PP-g-MAZn were discussed.The influence of the rheological properties byPP-g-MAZn were studied by using a rheometer.The polarizing light microscope(PLM) observation showed that the β nucleating agentcould induce the formation of βcrystal. Increasing content of the nucleating agent, whichincrease the content of βcrystal and perfect the crytal.The addition of β nucleating agent canincrease the βcrystal of the PP/Tale composite. The introduction of β nucleator of0.4%bymass made the Izod impact strength of the PP resin rise by8.6times to be the maximum at14.3KJ·m-2and the hardness reach80N·mm-2. With the increasing of β nucleating agentcontent,the processing property first decreased and then increased.The sudies in the propertiesof PP/Tale composite by PP-g-MAZn compatibilization indicated:with the increasing ofgrafting rate,the tensile strength of the composite system first raised and then got down andthe peak value reached40MPa when the grafting rate was9.7%.The Izod impact strengthwere on the decline and the hardness were gradually increasing when the grafting rateincreased. The tensile strength of PP/Tale composite increased gradually with increasing theusing amount of PP-g-MAZn, and the increment was1.2times. Meanwhile the impactstrength of the composite increased first, then decreased. When the using amount ofPP-g-MAZn was3.6%, the impact strength reached a maximum of7.1KJ·m-2. The processingproperties of PP/Tale composite became worse but the heat deformation temperature creasedgradually. The analysis result on SEM of PP/Tale composite containing compatibilizerPP-g-MAZn indicated that the PP-g-MAZn improved the dispersity of Tale in the PP resin.The study of the rheological properties showed that increasing the shear rate, the shearviscosity of PP/Tale/PP-g-MAZn composites was decreased. Under the same shearing rate, compared with PP/Tale composites, the results showed that the shear stress and shearviscosity values of PP/Tale/PP-g-MAZn composites were decreased slightly. WithPP-g-MAZn dosage increased, apparent viscosity of composite system was subtle changes.The viscous activation energy of PP/Tale/PP-g-MAZn composites declined as the increase ofshearing rate. The study of effect of extrusion elasticity showed that PP/Tale/PP-g-MAZncomposites was extruded without melt fracture phenomenon due to the addition ofPP-g-MAZn, the extrudate surface was smooth and its shear rate sensitivity decreased.In conclusion, the Izod impact strength of PP/Tale composite was enhanced obvioulywhen the content of β nucleating agent was0.4%.the addition of PP-g-MAZn ionomer couldimprove the dispersity of Tale in the PP resin.