Controlled Radical Polymerization Of MMA And VAC Mediated By Xanthene-9-thione And Thioxanthene-9-thione

The development of new controlled / living radical polymerization(CLRP) method is one of the hot research field of CLRP. In the controlled/living radical polymerization of MMAmediated by XANTHENE-9-THIONE, the reaction rate is faster, initial molecular weight is higher, increase of molecular weight is lower.St inhibits process in this polymerization system at initial stage. We try to add slight St to optimizeMMA radical polymerization mediated by AIBN/XT .The effects of St:MMA ratio, temperature and monomer concentration on polymerization system proves this polymerization system is living/controlled. We initiate the second monomer block polymerization by PMMA-XTmacromolecular initiator. The effect of PMMA-XT:St ratio,St concentration and temperature proves that block polymerization by PMMA-XTmacromolecular initiator can be controlled. We use THIOXANTHENE-9-THIONE mediating VAcradical polymerization,the effect of AIBN:TXTratio, VAc concentration and designed molecular weight can affect the preparation of PVAc-TXT macromolecular initiator,and initiateMMA block polymerization by PVAc-TXT macromolecular initiator.Slight styrene can affect MMA radical polymerization mediated by AIBN/XT.The ratio of St:MMA,temperature andmonomer concentration of MMA can significantly affect the reaction system.St:MMA ratio between 2 wt% to 4 wt% can optimize the polymerization process, When the ratio is as high as 6 wt%, GPC spectrum appears dual peak. This rule is also applicable in the Bulk polymerization of MMA. When the ratio of St:MMA is 4 wt%, temperature is 70 ?, Bulk polymerization of MMA of MMA can be controlled, reaction conversion increases from 10.4% to 50.1%, molecular weight increases from 6.1 k to 12.5 k linearly.We study the possibility of the second monomer polymerization initiated by PMMA-XT macromolecular initiator containing XT structure.When the ratio of PMMA-XT:St is 1:1, temperature is 75 ?,concentration of St is 20 wt%,polymerization can be controlled, reaction conversion increases from 3.6% to 82.6%, molecular weight increases from 3.0 k to 5.7 k linearly and achieves the theoretical molecular weight.TXT can mediate VAcradical polymerization,especially when the ratio of TXT:AIBN is 1:1.3,temperature is 75 ?, concentration of VAc is 30 wt%,polymerization can be controlled, reaction conversion increases from 2.9% to 11.1%, molecular weight increases from 0.9 k to 2.6 k linearly and PDI below 1.2.We study the possibility of polymerization of MMA initiated by PVAc-XT macromolecular initiator containing TXT structure It is the optimized to MMA polymerizationinitiated by PVAc-TXT macromolecular initiator that molecular weight increases from 13.2 k to 28.5 k when molecular weight of PVAc-TXT macromolecular initiator is 13.2 k, the temperature is 70 ? and the ratio of PVAc-TXT:MMA is 1:2.This study optimizes the controlled/living radical polymerization of MMA mediated by XT and uses TXT mediating VAc controlled/living radical polymerization, which promotes the CLRP application.