Conventional TPEs and TPRs do not have functional tack, but need to be adjusted by the compounding system to obtain the desired tackiness. With the continuous application of thermoplastic elastomers TPE and TPR, the adhesive properties (including self-adhesion and co-adhesion) of TPE and TPR may gradually be applied in different industries.
With regard to the stickiness of TPE materials, Dongguan Plastics Co., Ltd. talks about three different kinds of stickiness here:
1. TPE material self-adhesive; refers to the TPE material surface has a strong adhesive, similar to the surface coated with glue. This kind of TPE material with strong self-adhesion can be used for sticking everyday objects to prevent from falling or falling. Similar TPE materials, a foreign TPE manufacturer has special research and development, and applied for a patent. In fact, in the conventional TPE compounding system, adding a tackifier with good compatibility with the host compounding system can increase the surface tackiness of the TPE material. This type of stickiness is positive and is what users want and hope.
2. Toughness of soft TPE material surface. Some low-hardness TPE materials have a sticky feel on the surface of the soft TPE due to the high content of oil components in the compound. This sticky feeling is caused by the oil in the formula. SBS-based TPEs (TPRs) are generally more prone to surface tackiness problems, and such tackiness is negative and is what users want to eliminate.
3. Tackiness problems during overmolding. The viscosity mentioned here means that the TPE and the coated substrate (plastic) have similar solubility sp or good compatibility, and at the time of injection molding at a high temperature, the fusion bonding occurs on the bonding surface of the two materials. effect. Adhesion depends on the surface affinity of the TPE and the coated plastic (similar melting point, close polarity, surface tension, etc.)
The co-viscosity of TPE and TPR is too numerous to enumerate. Most plastics, a few non-metallic materials, and metals can be bonded to TPE and TPR in a manner similar to cohesion.
TOE adhesive ABS plastic
(1) Co-adhesion of TPE, TPR and plastics
This is the most common cohesion. TPE, TPR and plastic co-adhesive, in the industry have a more familiar name - plastic, also known as the second injection molding, overmolding, two-color / multi-color injection molding and so on. The application of TPE and TPR encapsulation can be seen everywhere in daily life. The co-adhesion effect of TPE, TPR and plastics depends on the difference in the polarity of the two materials and the surface tension of the plastic. At present, the industry can provide mature technology TPE, TPR products, and most plastics such as ABS, PA, PC, PP, PS, PCTG, PBT, etc. Good inter-adhesive (encapsulation).