How is Dongguan TPE ultra-soft transparent soft material?

TPE uses overmolding injection bonding process,

Thickness of TPE, TPR overmolding layer. In most overmolding applications, wall thickness in the range of 1.5-3.0mm ensures good adhesion. If the TPE layer is too thin, injection molding is difficult, adhesion strength is low, and feel is poor. If the TPE layer is too thick, on one hand the cost is higher, on the other hand it is prone to shrinkage, bubbles and other defects.

TPE transparent material requires high light transmittance, which necessarily demands strict surface quality of the product, without any defects such as streaks, pores, whitening, hazy halo, black spots, discoloration, poor gloss, etc. Therefore, during the entire injection molding process, strict and even special requirements must be placed on TPE raw materials, equipment, molds, and even product design.

TPE ultra-soft transparent soft material

Common products include handles, grips, electronic materials, etc. The material gives the products a comfortable touch, improves grip, enhances product appearance and added value.

TPE overmolding (two-shot injection molding) forming, the key point is to make TPE well bonded to the substrate materials such as PP, ABS, PC, PA, etc. To achieve good adhesion between TPE and the substrate,

Since any impurity in TPE material may affect the transparency of the product, attention must be paid to sealing during storage, transportation and feeding to ensure clean TPE raw materials. Especially if TPE raw material contains moisture, heating will cause the material to deteriorate, so it must be dried. During injection molding, a drying hopper must be used for feeding.

SEBS is the product after hydrogenation of SBS. SEBS has a saturated molecular structure, which leads to very different characteristics of SEBS. It has the necessary aging resistance, yellowing resistance and other properties required for producing transparent TPE, and also contributes to excellent properties such as high temperature resistance and corrosion resistance. Only then is transparent TPE manufactured.

TPE ultra-soft transparent soft material

According to the chemical principle of similarity and compatibility, the key is that TPE and the substrate should have similar polarity, so that molecular chain level fusion can occur between TPE and the substrate.

When using a regular injection molding machine to perform two-shot overmolding on nylon, it is recommended before overmolding,

To achieve the matte appearance of thermoset rubber, a rougher mold surface is required. Generally speaking, the rough surface produced by electrical discharge machining (EDM) results in excellent workpiece appearance and makes demolding relatively easy. Grinding methods such as steam blasting, sandblasting or shot blasting, as well as chemical etching, can also be used to produce surfaces with different gloss and appearance.

Transparent TPE, specifically thermoplastic elastomer, while TPR is translated from English, strictly speaking it is called thermoplastic rubber. This is the most basic difference. TPE is generally modified and formed from SEBS base material, while TPR is modified from SBS base material.

TPE ultra-soft transparent soft material

First preheat and bake the nylon part, because nylon has strong water absorption, and overmolding requires higher molding temperature; preheating before overmolding can remove moisture, facilitating quick hot overmolding.