One of the considerations for selecting plasticizer varieties for blown film-Plasticization
One of the considerations for selecting plasticizer varieties for blown film- Plasticizing property
The formula of blown film requires good plasticizing property and high plasticizing efficiency, otherwise it will make the surface blossom and have stripes, bubble is not allowed, even blown, can not pull the traction frame, etc. According to its plasticizing performance, dibutyl phthalate is the best. However, due to its volatility and water extraction, it ages very fast, especially the buried part of the agricultural film, which will harden rapidly, so it is not often used in the formula or a smaller proportion is considered. Dioctyl phthalate is a commonly used plasticizer. Because of its good performance, it is often selected by people. Petroleum ester can also be used instead of dioctyl phthalic acid vinegar, but the plasticizing performance and efficiency are poor. Therefore, if the same plasticization degree is to be achieved, the amount of petroleum Ester should be appropriately increased. Chlorinated paraffin has poor plasticizing efficiency, so the film is hard, but due to its low price and wide sources, appropriate proportion can also be considered in the formula. However, too much will make the bubble inaccurate and difficult to control due to poor plasticization, and there will be sweating during use (Precipitation)Phenomenon.
Dioctyl adipate, dioctyl sebacate and epoxy ester are also often used in blown film. Because their low temperature performance is ideal, adding appropriate proportion to the formula is of great benefit to the cold resistance of agricultural films. However, their plasticization performance is relatively poor. After adding more, the surface of the blown film will bloom and the thickness will be uneven. Moreover, their prices are also relatively expensive. Therefore, in general formulas, their total amount does not exceed ten. Related articles: plasticizer varieties used in PVC blown film