How to distinguish the quality of PVC profiles’plastic strips?

Plastic strips are widely used in steel, aluminum alloy profiles, and plastic doors and windows to install laminated glass and seal between door and window frames. Rubber and plastic product sealing strips are generally made of modified polyethylene raw materials.

The performance of the sealing strip greatly affects the airtightness, watertightness, heat loss and other key performance indicators of the doors and windows of the building glass and the firmness of the doors and windows. Therefore, my country has long formulated the industry standard GB12002-89 "Sealing Strips for Plastic Doors and Windows". Production and testing of standard sealing strips.

However, the quality and price of rubber and plastic seals for doors and windows in the current building decoration materials market are very confusing. The expensive ones are 15,000 to 6,000 yuan a ton, and the cheap ones are only 6,000 yuan a ton. The price difference is nearly 10,000 yuan, and the quality difference is very large, which makes people feel at a loss. Many sealing strip manufacturers claim that their products comply with the GB12002-89 industry standard, and can produce a test report that has passed the inspection of an authoritative department. According to our inspection of the rubber and plastic product sealing strips of well-known manufacturers currently used in the industry, and the sealing strip samples sent by related manufacturers, the results of the heating and weight loss state indicators in the hot air embrittlement performance item Shocking: more than 10 test products, none of them are qualified.

According to the requirements of the GB12002-89 specification, the index value of the heating weight loss state in the hot air embrittlement performance item of the plastic strip should be ≤3%. The heating weight loss state of the specific test results is: 7.17% to 22.54%. Far beyond the scope of industry standard requirements.

For such products, a lot of low melting point plasticizers or plasticizer substitutes are added to the formula. When such a product is new, its elasticity and flexibility are still very good. However, over time, when the plasticizer evaporates more, the elasticity and flexibility of the plastic strip will decrease, which will affect the sealing performance of the window and door at the slightest, and will affect the firmness of the assembly of the window and door at the worst.

In addition, the sealing strip with too high plasticizer content will cause plasticizer to transfer to the polyethylene profile that it contacts during the application process. Leads to partial coloring and solubilization of the frame and sash profiles. That is: on the profile cover that is in contact with the sealing strip, there is a dark brown pigment spot with different widths that cannot be wiped off or washed off, which is in obvious contrast with the snow-white profile body, which greatly affects the appearance. Due to the migration of plasticizers, the color traces partially protrude. (Sliding doors and windows are not exposed because the contact part between the sealing strip and the profile is not exposed, and the coloring and solubilization of the profile part are generally not observed. When the sliding door and window is in the open state, the sealing strip and the corresponding profile are out of contact, and the profile Partial coloring and solubilization are exposed.) Although the partial coloring and solubilization of the profile will not cause serious damage to the invalidity of the frame and fan profiles, it seriously affects the appearance of plastic doors and windows. This is a shortcoming after all, and it will have an extremely bad impact on the image of plastic doors and windows.

In order to better maintain the image of plastic doors and windows and care for the healthy growth of this new industry, manufacturers should produce authentic and qualified plastic strips, and plastic door and window assembly plants should choose authentic and high-quality products. Guarantee the quality of plastic doors and windows.