Synthesis Of Epoxide Polysiloxane And Its Application In Anti-scratch Polypropylene

The silicone material is a special polymer with semi-organic and semi-inorganic structure.Because of this characteristics,it is compatible and different from the C-C chain of the plastic when it is used as a plastic scratch-resistant agent,so that they can be mixed with each other and get a special effect.In this paper,I used hydrogen-containing polysiloxane,allyl glycidyl and three 1-olefins?1-octene,1-dodecene,1-octadecene?to synthesize three polysiloxanes?ALEP?containing epoxy and octyl or dodecyl or octadecyl.Then put these three ALEPs into polypropylene?PP?/barium sulfate?BaSO₄?and polypropylene?PP?/talcum powder to study the effect of improving the scratch resistance.I used hydrogen-containing polysiloxane with a hydrogen content of 0.25%reacted with allyl glycidyl ether and three 1-olefins respectively.In the reaction,the order of influence of the reaction conditions on the conversion rate and the product colour is:amount of catalyst>reaction temperature>reaction time>dropping rate of hydrogen-containing polysiloxane>n?Si-H?:n?C=C?.The optimum conditions for the synthesis of ALEP by the hydrosilylation reaction with platinum catalyst?H₂PtCl₆?are as follows:catalyst dosage 14 ppm,reaction time 6h,reaction temperature 80?,hydrogen-containing polysiloxane 60 min addition completion,n?Si-H?:n?C=C?is 1:1.2,the Si-H bond conversion rate of the synthesis reaction can be over 90%,and the structure of the product is characterized by FT-IR and ¹H-NMR.The Si-H bond disappears in the product,the alkyl group and the epoxy are can be successfully attached to the pendant group of the hydrogen-containing polysiloxane.After the addition of ALEP in the PP/inorganic filler system the melt flow rate of the system is obviously improved,and the improvement effect of the three kinds of ALEP is similar.It indicates the addition of ALEP can effectively improve the processing fluidity of the system and reduce the processing difficulty.After the addition of ALEP in the PP/TD,the impact strengthissignificantlyimproved,andtheimprovementorderis18-ALEP>12-ALEP>8-ALEP.18-ALEP was added to the plastic,the impact strength of the system was increased from 74.0 J/m to 99.5 J/m,which was more obvious than adding the same amount of 8-ALEP and 12-ALEP.18-ALEP was added to the PP/BaSO₄,the impact strength of the system was increased from 70.1 J/m to 90.5 J/m,which was more obvious than adding the same amount of 8-ALEP and 12-ALEP.After adding three kinds of ALEP additives to the PP/inorganic filler systems,the scratch resistanceis significantly improved,and the efficiency improvement order is18-ALEP>12-ALEP>8-ALEP.After adding 18-ALEP the change of gloss?L of PP/TD was increased from 2.33 to 1.76 compared no additives.After adding 18-ALEP the change of gloss in PP/BaSO₄ was increased from 2.05 to 1.60 compared no additives.