The raw materials of woven bags are generally various chemical plastic materials such as polyethylene and polypropylene. Plastic woven bags are made of polypropylene resin as the main raw material, which is extruded and stretched into flat wires, and then weaved and made into bags.
The production of woven bags is mainly polypropylene. Polypropylene is a thermoplastic resin obtained by polymerization of propylene.
1. Strong elongation: Polypropylene has high strength, large elongation, high initial modulus and excellent elasticity. Therefore, polypropylene fiber has good abrasion resistance. In addition, the wet strength of polypropylene is basically equal to the dry strength, so it is an ideal material for making fishing nets and cables.
2. Hygroscopicity and dyeability: light weight, good heat retention, almost no moisture absorption, but strong wicking ability, obvious moisture absorption and perspiration effect; polypropylene fiber has very little hygroscopicity, almost no moisture absorption, and the moisture regain under general atmospheric conditions is close to at zero. But it has a wicking effect, which transports water vapor through the capillaries in the fabric, but does not perform any absorption function itself. Polypropylene has poor dyeability and incomplete chromatogram, but woven bag whitening agent can be used. Moisture absorption, the moisture regain under general atmospheric conditions is close to zero. But it has a wicking effect, which transports water vapor through the capillaries in the fabric, but does not perform any absorption function itself. Polypropylene has poor dyeability and incomplete color spectrum, but woven bag brightener can be used.
It is often asked that in the production of white plastic woven bags, to achieve the whitening effect, is it better to use whitening agent or titanium dioxide? Titanium dioxide is a physical whitening agent, which belongs to covering and whitening, and adding too much will affect the tensile value of the product, while fluorescent whitening agent is optical whitening, which further improves the whiteness value of the product through optical effects. Generally, the dosage is relatively small, only need to add 200-300 grams of fluorescent whitening agent to one ton of plastic, plastic woven bags are recommended to use OB-1 special brightener for woven bags, the whitening effect is more obvious!