Types of woven bags

The main foreign production is polyethylene (PE), while the main domestic production is polypropylene (PP), which is a thermoplastic resin made by polymerizing ethylene. In industry, it also includes copolymers of ethylene with small amounts of alpha olefins. Polyethylene is odorless, non-toxic, and feels like wax. It has excellent low temperature resistance (up to -70~-100 ℃ for low use), good chemical stability, and can withstand most acid and alkali corrosion (not resistant to oxidizing acids). It is insoluble in general solvents at room temperature, has low water absorption, and excellent electrical insulation performance; But polyethylene is very sensitive to environmental stress (chemical and mechanical effects) and has poor heat aging resistance. The properties of polyethylene vary depending on the variety, mainly determined by its molecular structure and density. By using different production methods, products with different densities (0.91-0.96g/cm3) can be obtained. Polyethylene can be processed using the molding methods of general thermoplastic plastics (see plastic processing). It has a wide range of applications, mainly used to manufacture films, containers, pipelines, monofilaments, wires and cables, daily necessities, etc., and can also be used as high-frequency insulation materials for televisions, radars, etc. With the development of petrochemicals, polyethylene production has rapidly expanded, accounting for about 1/4 of the total plastic production. In 1983, the total production capacity of polyethylene in the world was 24.65Mt, with a capacity of 3.16Mt for under construction facilities.

Polypropylene (PP)

A thermoplastic resin made by polymerizing propylene. There are three configurations: isotropy, non isotropy, and intercropy. Industrial products mainly consist of isotropy. Polypropylene also includes copolymers of propylene and a small amount of ethylene. Usually a semi transparent colorless solid, odorless and non-toxic. Due to its regular structure and high degree of crystallization, it has a melting point of up to 167 ℃, is heat-resistant, and can be sterilized by steam, which is its outstanding advantage. Density of 0.90g/cm3, it is a lightweight universal plastic. Corrosion resistance, tensile strength of 30MPa, better strength, rigidity, and transparency than polyethylene. The disadvantage is poor low-temperature impact resistance and easy aging, but it can be overcome by modification and adding antioxidants separately.

The color of woven bags is generally white or gray white, non-toxic and odorless, and generally less harmful to human body. Although they are made of various chemical plastics, they have strong environmental protection and a large recycling capacity;

Woven bags have a wide range of uses, mainly for packaging and assembling various items, and are widely used in industry;

Plastic woven bags are mainly made of polypropylene resin, extruded and stretched into flat fibers, and then woven and bagged.

Composite plastic woven bags are made by compounding plastic woven cloth as the substrate through the casting method.

This series of products is used for packaging powdered or granular solid materials and flexible items. Composite plastic woven bags are divided into two in one bags and three in one bags according to their main material composition.

According to the sewing method, it can be divided into sewn bottom bag, sewn edge bottom bag, inserted pocket, and adhesive sewn bag making.

According to the effective width of the bag, it is divided into 350mm, 450mm, 500mm, 550mm, 600mm, 650mm, and 700mm. Special specifications are agreed upon by the supply and demand parties.