Study of the compatibility of hydrocarbon resins based on styrene, indene and alphamethylstyrene with SEBS block copolymer
In this work, three aromatic hydrocarbon resins based on styrene, indene and alpha-methylstyrene were cationically polymerized. These homopolymers were used in the preparation of blends with polystyrene-b-poly(ethylene-co-butylene)-b-styrene (SEBS) block copolymer to evaluate their compatibility. The polymers studied were polystyrene (PS), polyindene (PIn), polyalphamethylstyrene (PAMS) and SEBS. The blends were prepared by solution in toluene. The synthesized homopolymers were characterized by vibrational infrared spectroscopy (FTIR), gel permeation chromatography (GPC) and residual monomers by gas chromatography (GC-FID). The blends were characterized by rheological techniques through small amplitude oscillatory shear test (SAOS), dynamic-mechanical tests at low temperatures (DMA) and compatibility tests in solution through the determination of the cloud point (MMAP/DACP). The results showed that obtaining hydrocarbon resins from pure monomers in stirred tank reactors is perfectly possible at temperatures of 20 °C with precise controls of the insertion of loads (monomers/solvent), nucleophilic initiators (in this work H2O) and Friedel Crafts acid coinitiators (boron trifluoride in this work), obtaining low molecular weight amorphous homopolymers. Regarding the blends, it was possible to perform the homogenization by solution in toluene, thus obtaining the specimens for further characterization.