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SIS Polymer (Styrene-Isoprene-Styrene) for Hot-Melt Adhesives and Flexible Elastomeric Compounds
Overview
SIS polymer, also known as Styrene-Isoprene-Styrene (SIS) block copolymer or styrene-isoprene rubber, is a styrenic block copolymer (SBC) thermoplastic elastomer (TPE). In formulated systems, SIS polymer is commonly paired with hydrocarbon tackifier resins, plasticizing oils, and antioxidants to target specific viscosity, open time, and adhesion profiles. Guangju Yida is a reliable SIS polymer supplier for adhesive and compounding production.General Description
SIS polymer is a linear triblock structure (PS–PI–PS), where polystyrene (PS) end-blocks form physical crosslinks and the polyisoprene (PI) mid-block provides elasticity. These PS domains soften on heating, enabling reversible flow and easy reprocessing compared with vulcanized rubber. Industrially, SIS is commonly produced by living anionic polymerization: purified isoprene is polymerized first, followed by styrene addition to build the end blocks, then the polymer is finished, pelletized, and stabilized for processing. SIS can be melt-blended for hot-melt systems or dissolved for solvent-based adhesive manufacturing, depending on the target process.SIS Product Line of Guangju Yida
The following SIS polymer grade list is provided for quick specification alignment during sourcing, qualification, and formulation work at Guangju Yida.| Grade | ST% | Di-Block% | Tolune Solution Viscorsity (mPa ·s, 25 wt% in toluene; 25°C) | Meltfolw rate (g/10min, 200°C / 5.0 kg) | Alternative grades |
|---|---|---|---|---|---|
| SIS XJ-9015 | 15 | <1 | 1000-1500 | 8-16 | YH-1105 Sinopec Baling |
| SIS XJ-9116 | 16 | 16 | 700-1000 | 8-16 | YH-1106 Sinopec Baling |
| SIS XJ-9029 | 30 | <1 | 200-400 | 8-16 | YH-1209 Sinopec Baling |