The plastic sealing strip is steel, aluminum, plastic doors and windows, which are usually used to install the sealing window between the glass and the sealing material of the door frame fan. The high level of plasticizer seal will contact with the migration of plasticizer of PVC profile in use. Local colored frame and fan profiles and swelling are caused. Do not rub and wash away the black spots, which form a sharp contrast with the white fuselage shape and greatly affect the beauty. In terms of color, due to the traces of plasticizer, the local coloring visit and swelling phenomenon are exposed. Although the local distribution of coloring and swelling has seriously affected the beauty of plastic doors and windows. After all, this is a defect, which has a very bad impact on the image of plastic doors and windows. Visually inspect and identify the quality of rubber strips from the aspects of appearance strength, smell, combustion and observation:

Poor quality polyvinyl chloride (PVC) sealing strip has rough surface, large deformation, poor strength, and will crack and break when broken. It has a pungent aromatic smell. After the combustion self-extinguishing, the drawing is very short due to more fillers and less resin.

Vulcanized EPDM sealing strip has strength, good elasticity, small deformation, bright surface and high specific gravity (about 1.5). The flame root is blue and smokeless when burning, and the residue is not sticky. It cannot be drawn after burning.

The performance of thermoplastic EPDM sealing strip is similar to that of vulcanized EPDM sealing strip. The surface is matt and the handle is light (specific gravity 0.90~-0.95). The residue after combustion is sticky.

The performance of the sealant strip has significantly affected the airtightness, water tightness, heat loss and other important performance indicators of thick doors and windows, as well as the degree of doors and windows. For this reason, developed countries have a long national standard GB12002-89 "Sealant strip for plastic doors and windows". Standardize production and inspection seals. EPDM rubber sealing strip is soft and elastic. It can almost reach twice the stretching length without breaking. It can recover quickly after releasing.