For traditional inferior PVC seals, you need to understandFor traditional inferior PVC seals, you need to understand
PVC is polyvinyl chloride, a plastic product synthesized from 43% oil and 57% salt. Compared with other types of plastic products, PVC uses raw materials more effectively and reduces fuel consumption. At the same time, the energy consumption of PVC manufacturing is also very low. And in the later period of use of PVC products, it can be recovered and converted into other new products or incinerated to obtain energy.
So how to judge the inferior PVC sealing strip, the following summarizes several judgment methods for you.
1. The appearance of oil seepage on the surface appears, the waste engine oil is not compatible with PVC at all, and the surface of the sealing strip is prone to grease, and yellow marks are also stained on the surface of the light-colored wooden door stop and the door leaf, causing product pollution or even Not environmentally friendly has many volatile substances that pollute the air.
2. When those so-called plasticizers evaporate or ooze out, the sealing strip will lose its original flexibility and become very stiff, and it will soon age and shrink, shrinking in length, shrinking in cross section, so that the wooden door is closed There is a big gap in some parts, and the tightness becomes very poor (water leakage, dust leakage), until the loss of the sealing and sound insulation effect, increasing the cost of air conditioning and heating, without the buffering effect, the life of the wooden door will be greatly reduced .
First, use your nose to smell whether there is an odor. The general PVC sealing strip will have a very pungent odor. The normal silicone rubber sealing strip will only have a little alcoholic smell. The smell is very small and almost not smelled. .
Second, put the PVC sealing strip and the silicone rubber sealing strip at a high temperature for a period of time (on the roof or in a sunny place), the PVC sealing strip will become very soft in a short time, and the grease on the surface of the sealing strip will precipitate out. Contaminated with dust, and yellowed (oil is easy to absorb soil), oil seeps, dirty hands; silicone rubber seals have no change in physical properties, and the pressure ring for household pressure cookers is silicone rubber, which uses silicone rubber High temperature resistance and non-toxic environmental protection performance, silicone rubber in 200 ℃ working environment, physical properties have no significant changes.
3. Put the PVC sealing strip and the silicone rubber sealing strip in the freezer compartment of the refrigerator at the same time for a few hours. The PVC sealing strip will become stiff and easy to break, and the physical properties of the silicone rubber sealing strip will not change. There is no obvious change in physical properties of silicone rubber at -50℃.
Fourth, some cheaper sealant fillers will be a lot, so the surface will not be very bright, the color is dull, the cut off seal will be rough, the feel will be stiff, the pull will be almost inelastic, the silicone rubber seal will be bright, Soft to the touch, stretch is extremely elastic, cut off the sealing strip, and the cross section is exquisite and shiny.
Fifth, burning, the PVC sealing strip will foam, shrink, and emit black pungent smoke. The combustion is insufficient, leaving hard plastic material residue.
Six, depending on the specific gravity, how many meters can be produced per kilogram. Vendors of PVC sealing strips have made a lot of efforts in using fillers, and some seek to achieve greater output. (Save a little electricity) The use of talc, heavy calcium and the like as fillers has greatly increased the production of sealing strips. The proportion, (usually our users are mostly bought in kilograms, used according to length), this invisibly increases the cost, and reduces the quality. After adding heavy calcium PVC sealing strips, you stretch it back and forth several times by hand, and a small amount of white powder will appear on the surface. The density of the PVC seal should be 1.4-1.6. Silicone rubber seals use nano-scale silica for filling and reinforcement, light texture, density ratio between 1.1-1.25, so the output rate is 20% more than PVC seals.