Styrenic Block Copolymers (SBC, TPS, TPE-S)
Hot-melt pressure sensitive adhesives can form a coating in its molten state and rapidly bond under light pressure after it is cooled. It can be peeled off easily without contaminating the surface of the adhered substrate. Hot-melt pressure sensitive adhesives are mainly made of a thermoplastic elastomer (TPE, e.g. SBS, SIS), tackifying resin, anti-oxidant and filler. Using saturated TPE (e.g. SEBS and SEPS, produced by the hydrogenation of SBS or SIS) in the making of hot-melt pressure sensitive adhesives increases the oxidation resistance, UV resistance and heat resistance of the adhesive, and improves its weatherability. SBS can also be used to make solvent based adhesives featuring high initial bond strength, high viscosity, and long open time.
Using TPE to modify conventional asphalt can extend its service temperature, improves its mechanical properties, increases the asphalt’s cold temperature flexibility and enhances its ageing performance. When used in road construction, TPE-modified asphalt in combination with the proper asphalt mix can improve road safety by increasing the road’s load handling capacity. When applied in roofing and waterproofing works, TPE-modified asphalt bonds better to the structure, is less likely to have vertical flow and ages better to help reduce the high cost of maintenance and repair.
TPE is commonly used to toughen engineering plastics. TPE modified plastics show better impact strength and low-temperature resistance. TPE film added with nanoparticles has improved gas barrier properties and is extensively used in food and beverage packaging, and in precision filter infusion bags. The addition of a compatibilizing agent and polar plastic in TPE enhances the compatibility of TPE with dissimilar materials. For example, the addition of maleic anhydride (MAH) grafted SEBS and TPU enables TPE to bond with nonwoven fabrics to produce synthetic leather and various textile composites.
Grafted SEBS is used mainly in the modification of engineering plastics, such as polyamide (PA), ABS, polycarbonate (PC) and PET to increase the toughness of the material. It is also used as a compatibilizing agent in the modification of engineering plastics to enhance miscibility between materials. Adding only a small amount of grafted SEBS improves the toughness of engineering plastic markedly and increases their impact resistance. The combination of grafted SEBS and other SEBS polymers results in stable copolymers with excellent oxidation and UV resistance.
SBS is used extensively in TPR shoe soles. It can replace vulcanized rubber and polyvinyl chloride based shoe materials. SBS shoe soles have excellent elasticity, aesthetic colors, good anti-slip, gas barrier, wear resistance, flexing endurance and low-temperature resistance properties. The coefficient of friction of SBS shoe soles on an asphalt road surface and wet/drenched road surface is much higher than shoe soles made of other materials. Another feature of SBS is its environmental friendliness. Waste SBS shoe soles can be recycled and reprocessed. SBS shoe soles are moderately priced and available in a variety of styles. They can be semi-clear, imitation ox-tendon soles, colorful dual-color soles, or lightweight foam soles.