| In this paper,polypropylene(PP) was modified by solid-phase graft copolymerization with maleic anhydride(MAH),styrene(St) and butyl -acrylate(BA),using benzoyl peroxide(BPO) as an initiator and xylene as an interfacial agent.The grafting ratio and grafting efficiency of PP-g-(St-MAH) was determined by chemical titration and degradation of PP during the graft reaction was investigated by measuring the melt flow rate(MFR).The applications of the grafted PP as bonding agents and compatibizers for PA6/PP and calcium carbonate filled PP composites were studied.In preparation process,the best condition is:premixed time is 1.5h, xylenel is 5phr,BPO is 2.5 phr,,MAH is 10 phr,St is 2.5 phr,,reacting 1.5h at 110℃,the grafting ratio could reach 6.15%and grafting efficiency could reach 65.53%.Simultaneously,PP-g-(MAH-co-St-BA) ternary system was studied and found out that the ternary system of grafting yield is not higher than binary system PP-g-(MAH-co-St).At bonding applications,a variety of technologcial conditions such as pressure and time had an influence on the shearing strength and racking strength.It was mainly studied the different grafting properties under different grafting ratios and different melt flow rate.In addition, the change of adhesion property after adding these auxiliary was also contrasted through added paraffin wax or SBS into PP-g-MAH.The results showed that the adhesive strength is the best which compressed under the pressure of 4 MPa for 8 minutes.The racking strength increases when mixing paraffin wax with PP-g-MAH and fluid flow rate increases,while the shearing strength shows no apparent difference. Adding SBS into PP-g-MAH can made adhesive strength increase. PP-g-(MAH-co -St-BA) ternary system's peel strength of body is stronger than PP-g-(MAH-co-St)(or PP-g-(MAH-co-BA)).Grafted PP has found compatibilization effect in PA6/PP and PP/CaCO3 composite system,and mechanical properties of composite system is improved.
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