The extrusion hose produced by EPDM rubber or EPDM reclaimed rubber has excellent resistance to aging and high and low temperature resistance and can be used in special environments. However, EPDM hoses often encounter the surface of extruded hoses without light during the production process. The problem directly affects the sales of hoses; what are the reasons for the appearance of the EPDM extrusion hoses that are not bright, and how to solve this problem? How much do you know how to improve the surface brightness of EPDM extrusion hoses?
The EPDM hoses on the market are mostly black, which causes many reasons for the black hose surface to be unlit. It can be started from the choice of raw materials and formula design.
The main raw materials of EPDM hose are EPDM rubber and EPDM reclaimed rubber. EPDM rubber is a terpolymer of ethylene, propylene and non-conjugated diene. It has excellent aging resistance and erosion resistance and ethylene content. The higher the hardness, tensile strength and tear resistance of the EPDM vulcanizate, the better the rubber with high ethylene content in the EPDM hose formulation can improve the smoothness of the hose surface; use EPDM Recycled rubber produces smoother extruded hoses with higher fineness and lower impurity content. The smoother the hose surface is produced.
Use EPDM/recycled rubber and improve the blending ratio of the original rubber in the formula to improve the smoothness of the surface of the EPDM hose. Carbon black is the most commonly used black powder-like reinforcing agent in the rubber product industry. Carbon black is the main rubber hose. Reinforcing filler can improve the surface brightness of black EPDM hose; calcium carbonate and talc in rubber filler can improve the surface finish of rubber compound, and can increase the amount of calcium carbonate and talc powder properly under the condition of mechanical properties; improve the surface light of EPDM hose Brightness can also use high flash point paraffin oil or hydrogenated naphthenic oil; rubber hose processing enterprises can also use appropriate amount of dispersant or rubber brightener, wherein the rubber brightener can significantly improve the appearance brightness of EPDM hose.
3. Extrusion speed
When EPDM rubber and EPDM reclaimed rubber are used to produce hoses, the compounding process and extrusion process of the rubber compound will also affect the smoothness of the hose surface, especially the rubber tube extrusion speed, and the extrusion speed can also improve the EPDM. The brightness of the hose surface; however, since lowering the extrusion speed affects the production efficiency, it is better to use calcium carbonate or talc in the formulation.
The production cost of pure EPDM rubber production hose is high. The rubber tube with high index of pure EPDM reclaimed rubber production may not meet the relevant standards. At this time, EPDM rubber and EPDM will be regenerated. The combination of glue is an ideal production method. There is still a lot of problems to be aware of in the production of rubber hoses for EPDM/recycled rubber. Xiaobian will come to you later.