Study On Prqierites Of PP-g-AN/PP On Condiiton Of Hypothermic And Itiermal Oxidaitve Ageing Treatment

In this paper，through polypropylene (PP) modifing of acrylonitrile，the main chain of PP wasgrafted by acrylonitrile to enhance the internal chain structure and improved anti-agingproperties. The performance index of PP/PP-g-AN copolymer can accord with the demands ofthe aging resistance of polypropylene.In this paper, high grafting ratiol PP-g-AN was prepared by solid phase grafting in theautoclave and tested the grafting ratiol through Kjeldahl determination. Studied PP-g-AN/PPblending ratio and the effect of anti-aging properties of PP under low temperature, thermaloxidative ageing treatment.And tested and analysised the blends’ melt index and rheologyproperties.At the first place, copolymer of acrylonitrile which grafted onto polypropylene(PP-g-AN) was prepared by the methods of solution grafting. Using with different massfraction of the grafted copolymer and pure polypropylene which were blended as thepre-planed copies of PP-g-AN injected to stander samples and did freezing and thermaloxidative ageing treatment. Then we took some tests for melt flow rate (MFR) and rheologyof the frozen samples and untreated blank samples. Meanwhile we found that the graftcopolymer had the inhibition effect on polypropylene’s degradation and aging. In short, theperformance indicators of the blends’ anti-aging were superior to the virgin PP under the sameaging conditions.The results showed that the grafted copolymer (PP-g-AN) grafting ratio could reachmore than7%; when the PP-g-AN/PP best blending ratio reached6%, the PP internal chainstructure could be fully improved and the tensile strength was improved; as the freezing timeincreased, the tensile properties was stable, so as to achieve the purpose of anti-agingproperties of PP at a low temperature. Last but not least, when PP-g-AN/PP best ratio reached6%，the toughness of polypropylene had improved a lot in the aspects of anti-aging at lowtemperature as the graft coplymer brought in，when PP-g-AN/PP best ratio reached6%，thetoughness of polypropylene had improved a lot in the aspects of anti-aging at thermaloxidative ageing as the graft coplymer brought in.