What special requirements does the combination of reinforced nylon and TPE soft glue bring when manufacturing such Instrument and Device Shell?

The combination of reinforced nylon and TPE soft glue does bring a series of complex and specific special requirements when manufacturing Instrument and Device Shell. These requirements not only involve the selection and processing of materials, but also include the optimization of injection molding process, the adjustment of mold design, and strict quality control. The difference in polarity between nylon and TPE soft glue may lead to weak bonding between the two. In order to improve the compatibility between them, it is usually necessary to add a grafting agent or a compatibilizer to improve the interfacial interaction between TPE and nylon, thereby enhancing their bonding. Specific types of TPE have good compatibility with nylon, but the hardness range may be limited. Therefore, when selecting TPE, it is necessary to comprehensively consider its hardness, elasticity, wear resistance and other properties as well as its compatibility with nylon.
Before encapsulation, nylon parts need to be preheated or baked to remove moisture and stress inside them, while increasing the temperature of the material surface, which is conducive to the fusion of TPE and nylon. The preheating temperature and time should be adjusted according to the type and thickness of nylon. After baking, nylon parts should be encapsulated quickly to avoid long-term exposure to air, which may cause surface cooling and oxidation.
The molding temperature of TPE should be higher than its melting point but lower than the decomposition temperature of nylon to ensure that TPE can fully melt and flow during the injection molding process while avoiding nylon decomposition. The injection pressure should be high enough to ensure that TPE can fully fill the mold and fit tightly to the surface of the nylon part. However, too high injection pressure may cause mold deformation or nylon part rupture.
The mold design needs to consider the fluidity and fusibility of TPE and nylon to ensure that the two materials can be evenly mixed and form a good bonding layer during the injection molding process. The cooling system of the mold should be reasonably designed to ensure that TPE and nylon can be quickly cooled and solidified during the injection molding process to avoid deformation and shrinkage.
When using a cold runner injection system, the runner design should be as simple and smooth as possible to reduce the flow resistance and residence time of the melt in the runner. The cross-sectional size and shape of the runner should be adjusted according to the fluidity and injection pressure of TPE to ensure that the melt can smoothly fill the mold and form a good bonding layer.
The finished product needs to be tested for bonding strength to ensure that the bond between TPE and nylon is firm. Test methods include peel test, tensile test, etc. The results of the bonding strength test should meet the relevant standards or customer requirements to ensure that the shell will not fall off or be damaged during use due to poor bonding. The shell of the instrument and equipment may be exposed to the outdoor environment, so weather resistance tests are required, including UV aging test, salt spray test, etc. The results of the weather resistance test should show that the shell can still maintain good performance in harsh environments, such as color stability, hardness retention rate, anti-aging performance, etc.
The finished product must comply with environmental protection testing standards such as ROHS, PAHS, REACH, etc. to ensure that the shell does not contain harmful substances and meet the environmental protection requirements of developed countries and regions such as the United States, Japan, and the European Union. Environmental testing should be carried out regularly to ensure that the raw materials and finished products in the production process meet environmental protection standards. The finished product should be inspected for appearance to ensure that the surface of the shell is flat, free of scratches, bubbles and other defects. The size inspection should ensure that the size of the shell meets the design requirements, including thickness, length, width, etc.