Effects of compatibility between tackifier and polymer on adhesion property and phase structure: Tackifier-added polystyrene-based triblock/diblock copolymer blend system

• Published in: Journal of applied polymer science Vol. 120; no. 4; pp. 2251 - 2260
• Main Authors: Nakamura, Yoshinobu, Adachi, Manabu, Ito, Keiko, Kato, Yosuke, Fujii, Syuji, Sasaki, Mariko, Urahama, Yoshiaki, Sakurai, Shinichi
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 15.05.2011; Wiley; Wiley Subscription Services, Inc
• Subjects: Adhesion; adhesives; Agglomerates; Applied sciences; Blends; block copolymers; Copolymers; Exact sciences and technology; Forms of application and semi-finished materials; Materials science; morphology; Peel strength; Polyimide resins; Polymer industry, paints, wood; Polymers; Polystyrene resins; SAXS; Solid phases; Technology of polymers; Tackifying resin; block copolymers; Adhesivity; Diene polymer; Polymer blends; adhesives; Mechanical properties; Thermoplastic rubber; adhesion; Experimental study; Diene copolymer; SAXS; Triblock copolymer; Dynamic mechanical properties; Peel strength; Morphology; Concentration effect; Isoprene copolymer; Diblock copolymer; Surface properties; SIS; Adhesive; Resinic acid; Styrene copolymer
• ISSN: 0021-8995; 1097-4628; 1097-4628
• DOI: 10.1002/app.33442

The effects of compatibility of tackifier with polymer matrix and mixing weight ratio of triblock/diblock copolymers as the matrix on the adhesion property and phase structure of tackifier-added polystryrene triblock/diblock copolymer blends were investigated. For this purpose, polystyrene-block-polyisoprene-block-polystyrene triblock and polystyrene-block-polyisoprene diblock copolymers were used and the diblock weight ratio in the blend was varied from 0 to 1. Spherical polystyrene domains with a mean size of about 20 nm were dispersed in the polyisoprene (PI) continuous phase. In the case of the hydrogenated cycloaliphatic resin as tackifier having a good compatibility with PI and a poor compatibility with polystyrene, the peel strength increased with an increase of the tackifier content, and the degree of increase became significant above 40 wt % of tackifier. It was found that the nanometer-sized agglomerates of tackifier in the PI matrix were formed and the distance between the nearest neighbors of agglomerates was about 15 nm from SAXS measurement. The peel strength increased with an increase of the nanometer-sized agglomerates of tackifier from TEM observation. On the other hand, in the case of the rosin phenolic resin as tackifier having a good compatibility with both polystyrene and PI, the peel strength increased effectively at the lower tackifier content, while no significant increase at higher tackifier content was observed. The agglomerates of tackifier were never confirmed in this system. The higher peel strength was obtained at the diblock weight ratio in the blend of 0.5-0.7 for both tackifier-added systems.