The raw materials for plastic woven bags include PP (polypropylene) and PE (polyethylene), and the PP market is relatively flat. The transaction atmosphere did not respond very well. The slump in the PP market may be related to the off-season of the woven bag market from May to September each year, where low demand naturally leads to low trading volume. Of course, with the continuous decline of crude oil prices and the unstable mentality of some markets, some PP market prices have slightly declined, but the overall market situation has not changed much and the impact is minimal. In the coming months, the editor believes that there is limited room for the PP market to rise in transaction volume. Without special circumstances, the market will maintain a stable state for a long period of time. Plastic woven bags have the characteristics of light weight, good electrical insulation, good corrosion resistance, and easy processing and molding. Plastic woven bags have certain general characteristics of PP and their own characteristics. As follows:
1. Lightweight
PP is usually relatively light, and the density of PP woven bags is about 0. 9-0。 98 grams per cubic centimeter. Commonly used plastic woven fabric, if no filler is added, is equal to the density of plastic. The density of plastic used for plastic weaving is 0. 9-0。 91 grams per cubic centimeter. Usually, woven fabrics are lighter than water.
2. High fracture strength
Plastic braid is a flexible material with high breaking strength in plastic products, which is related to its molecular structure, crystallinity, drafting orientation, etc., as well as the type of additives. If specific strength (strength/specific gravity) is used to measure plastic braid, it is higher than or close to metal materials.
3. Good chemical corrosion resistance
Plastic woven fabric has good corrosion resistance to inorganic and organic materials. Below 110 ℃, it has no effect on it for a long time. It has strong chemical stability to solvents, grease, etc. When the temperature increases, carbon tetrachloride, xylene, turpentine, etc. can swell it. Fuming nitric acid, fuming sulfuric acid, halogen elements, and other strong oxides can oxidize them, and they have good corrosion resistance to strong alkalis and usually acids.
4. Good wear resistance
The friction coefficient between pure plastic woven fabrics is small, only 0. Around 12, similar to nylon, to some extent, the friction between plastic woven fabric and other items has a lubricating effect.
5. Good electrical insulation
Pure plastic woven fabric is an excellent electrical insulator. Due to its non hygroscopicity, unaffected by humidity in the air, and high breakdown voltage, its dielectric constant is 2. 2-2。 6. Its volume resistance is very high, and the insulation of plastic woven fabric is good, which does not mean using it as an insulation material.
6. Environmental resistance
At room temperature, plastic woven fabric is actually completely free from moisture erosion, and its water absorption rate is below 0 within 24 hours. 01%, water vapor penetration is also very low, and at low temperatures, it becomes brittle and prone to cracking. Plastic woven fabric will not undergo mold.
7. Poor anti-aging ability
The aging resistance of plastic woven bags is poor, especially PP woven bags are lower than polyethylene woven bags. Its aging problems are mainly thermal itching and photodegradation. The poor anti-aging ability of plastic woven fabric is one of its main shortcomings, which affects the service life and application fields of woven bags.