The raw material of ton bags is polypropylene, and the raw materials for producing polypropylene are natural gas, petroleum, and coal. Coal is first used to make gas, and petroleum is used to refine naphtha. Then the gases from natural gas, coal gas, and naphtha cracking are separated. The separated methane (C1) can be used as fuel, ethylene (C2) can be used to produce products such as polyethylene, and propylene (C3) can be used to produce products such as polypropylene, butylene, etc. Alkenes (C2), etc. can produce rubber, etc., and other gases (Cs~Cg) have other uses.
Propylene (also known as propylene monomer) is then polymerized into polypropylene. When polymerizing polypropylene, Ziegler-Natta catalyst is used to produce crystalline isotactic polypropylene with a regular structure. According to the polymerization type, it can be divided into four categories, namely solution method, solvent method, bulk method, and gas phase method production process. The original polypropylene production process has the following processes: polymerization, separation and monomer recovery, deashing, removal of random matter, drying, granulation, etc., which is called a first-generation process. The second-generation process omits the deliming process, while the third-generation process streamlines the deliming and random matter removal processes.
One of the main raw materials for making ton bags is PE. High temperature-resistant ton bags made of PE are easy to age. This is a headache and not durable. Ton bags made of PP crystalline materials are much harder than those made of PE, and they are The melting point of PP is relatively high, because the aggregate PP is relatively fragile at temperatures above 0 degrees Celsius, so many PP materials sold have a few hundredths of irregular aggregates or have a higher ethylene content. Lead aggregate, polymer PP material has a lower heat distortion temperature, lower transparency, lower gloss, and flexibility, but it has relatively strong impact strength and can withstand large impact pressure. It is Because of this relatively high crystallinity, the surface stiffness and scratch resistance of the material are relatively good. However, the price of this material when made into high-temperature resistant ton bags is relatively high.