A special TPE with high adhesive TPE coated PC raw materials
Source：德创化工Time：2020-06-03Hits：1879
Thermoplastic elastomer TPE is a material with the characteristics of high elasticity, high strength, high resilience of rubber and injection molding. The invention has the advantages of environmental protection, innocuity, safety, wide hardness range, excellent coloring property, soft touch feeling, weather resistance, fatigue resistance and temperature resistance, excellent processing performance, no need of vulcanization, recycling, cost reduction, secondary injection molding, coating and bonding with PP, PE, PC, PS, ABS and other matrix materials, and can also be formed separately.
I. Concept of TPE Encapsulation:
TPE encapsulation, as the name implies, is to encapsulate TPE soft adhesive materials onto other materials. Generally used processing methods include two-color injection molding machines for one-step molding, or ordinary injection molding machines for two-step injection molding using encapsulated molds. TPE coated molded products are generally handles and handlebars. Because of the special comfortable touch feeling of TPE soft adhesive material, the introduction of TPE material improves the grip and touch feeling of the product.
Second, TPE material concept:
TPE material is a general term for Thermoplastic Elastomer and its English full name is Thermoplastic Elastomer. It is a kind of functional material with rubber elasticity and plastic stiffness, which can be directly injection molded. Generally, the TPE material coated with rubber refers to TPE-S, i.e. polystyrene thermoplastic elastomer, which is a thermoplastic engineering plastic obtained by composite modification based on sebs or SBS elastomer. TPE-S elastomer is also commonly called TPE or TPR in the elastomer industry.
Three, TPE coated PC material characteristics:
TPE thermoplastic elastomer is SEBS rubber modified material, which has rubber elasticity and can be conveniently injected or extruded. The hardness range of the rubber compound can be adjusted at Shorea 0-100 degrees. The common hardness of TPE compound used for encapsulating PC ranges from 30 to 80 degrees, and its appearance is natural color or translucent particles. The rubber compound has excellent wear resistance and good adhesion to PC coating, and the finished product feels comfortable and smooth.
4. Processing Method of TPE Encapsulated PC:
TPE coated PC generally adopts the conventional molding method, i.e. two sets of molds, one for injection molding PC products and the other for injection molding TPE compound onto the surface of PC products. This type of molding method is called secondary injection molding, overmolding or insert injection molding. It can also be processed by a more advanced two-color injection molding machine. The results are the same. TPE and PC are well bonded together by injection molding. The injection temperature of glue coating is different according to the hard glue material. Due to the temperature, both hard glue and TPE soft glue should be softened to promote the compatibility of the two materials at the contact surface. In order to achieve the true encapsulation effect, the injection temperature of TPE encapsulated PP material is usually about 170-190 degrees Celsius. The encapsulated ABS material is about 220-220 degrees Celsius. The temperature of encapsulated PC material is slightly higher than the injection temperature of encapsulated ABS.
Fifth, the main advantages of TPE application in adhesive coating are as follows:
TPE elastomer soft glue is used for secondary injection molding, and is coated with glue and glued. Because TPE material has good skid resistance and good elastic touch, it can improve the touch feel of products and enhance the grip.
TPE elastomer soft adhesive can be adjusted to appropriate hardness (hardness range Shore 25-90A) and appropriate physical properties (such as abrasion resistance, scratch resistance, cohesiveness, melt index, etc.) according to the physical property requirements of the product. Various possible material application schemes are provided for different products.
TPE is coated with glue and shot-glued. Commonly used products such as handles, grips, electronic materials, etc. The material endows the product with comfortable tactility, improves the gripping property, improves the beauty of the product and the added value of the product. Most of the products are exported to the United States, JPN, EU and other developed countries and regions. Because TPE elastomer soft rubber is a green and environment-friendly raw material, the material does not contain phthalate, halogen and 38 SVHC substances of very high concern specified by REACH. According to RoHS, REACH, NP, EN71 and PAHs environmental protection testing standards, it can fully meet the environmental protection requirements of developed countries and regions such as the United States, JPN and EU.
Six, TPE coating materials are:
TPE can be firmly bonded with common general plastics PP,GPPS,HIPS,ABS and engineering plastics PC,PC/ABS,PA and their modified materials, or can be formed separately.
Seven: TPE Encapsulated PC Application:
TPE-coated PC is mainly used for coating electronic and electrical accessories such as hardware tool handles, mobile phone protection covers, game console handles, interphone housings, instrument housings, etc. Generally, TPE with hardness of 60~80 degrees is used for encapsulation of such products, while TPE compounds with different hardness and physical properties may be used for other special products.
