Preparation method of strong-autohension polyethylene preservative film

Abstract

The invention discloses a preparation method of a strong-autohension polyethylene preservative film. According to the invention, dioctyl phthalate and dioctyl adipate which are used as plasticizers are combined, and inorganic filler barium carbonate and aluminum oxide are combined, and then the extensibility and the obdurability of the preservative film are improved, so that the autohension of the preservative film is enhanced. The preparation method comprises the following steps: sequentially adding every component into a thermal mixer; starting up the thermal mixer, stirring the materials at high speed when the temperature rises to 90-100 DEG C for 10-14 minutes and then discharging the materials; introducing the materials into a low-speed cold mixer, stirring, reducing the temperature by using jacket cooling water in the cold mixer, and then discharging the materials; pre-heating a threaded rod and a cylinder head grinding tool in an extrusion film blowing machine to 115-125 DEG C, and then adding the mixed materials into the threaded rod in the extrusion film blowing machine for film extrusion.

Description

technical field [0001] The invention relates to the technical field of packaging materials, in particular to a preparation method of a polyethylene fresh-keeping film with strong self-adhesiveness. Background technique [0002] At present, commercially available plastic wrap can be divided into three categories according to different raw materials: the first category is polyvinylidene chloride (PVDC), which is mainly used for the packaging of cooked food, ham sausage and other long-term and large-scale industrial products; It is polyethylene (PE), which is mainly used for the packaging of ordinary fruits, vegetables, etc.; the third category is polyvinyl chloride (PVC) that people use more. Among them, polyethylene and polyvinyl chloride cling film are widely used in daily life. From vegetables, fruits to temporary fresh-keeping of household food, and to prevent food from smelling when stored, cling film must be used. The self-adhesiveness of the plastic wrap mainly depends...

AI Technical Summary

Problems solved by technology

[0004] 1. The problem of monomers, polyvinyl chloride inevitably has residual vinyl chloride monomer (VCM) during polymerization, and excessive concentrations will cause serious harm to the human body (damage to the nervous system, liver and embryos);

[0005] 2. The problem of additives. During the production of polyvinyl chloride cling film, various additives (stabilizers, plasticizers, etc.) need to be added. They are exposed to oily food for a long time, especially when the temperature is high in summer, it is easy to migrate and precipitate from the cling film. , infiltrate and remain in food, causing harm to human health;

[0006] 3. Environmental protection issues. PVC itself cannot be biodegraded. Under the action of light / heat, the degradation is also very slow. If it is incinerated, it will produce a large amount of irritating and corrosive gases. When the combustion is not complete, it will also produce dioxins and other serious problems. carcinogen

[0007] However, the stretchability of PE cling film is not enough, it is easy to break; and there is a serious deficiency in self-adhesiveness, self-adhesiveness is not strong, it is difficult to use on plastic boxes, and the packaging speed is slow, which is not conducive to mechanized packaging