ASYMMETRIC MULTI-BLOCK SBS POLYMER AND PREPARATION METHOD THEREOF

摘要

PURPOSE: Provided is a multi-block SBS polymer which has excellent solubility in an adhesive resin and oil, thereby being able to reduce the processing time for preparing adhesives. Also, the multi-block SBS polymer has excellent adhesive properties such as loop initial adhesiveness, 180 deg.C peel strength, adhesiveness keepability with a proper level of heat resistance, and is easy to control its molecular weight due to the inhibition of side reactions. CONSTITUTION: The asymmetric multi-block SBS polymer is characterized by having a structure of mB1*S1-lB2-S2-sB3, wherein B is butadiene block, S is styrene block, l, m, s are relative size of blocks, specifically a greater size, medium size, and small size, respectively, and * is a taper block present between mB1 block and S1 block, satisfying the following equations: (a) 0.01(lB2)<=mB1<=0.5(lB2) and 0.01(mB1)<=sB3<=0.5(mB1), (b) 0.5S1<=S2<=1.5S1, and (c) 5%<=*%<=25%, wherein *% is a ratio of the taper block to the total styrene block.