What are the reasons for the hardening of plastic products in winter?

What are the reasons for the hardening of plastic products in winter? Below Hubei health care products plastic bottle manufacturers to introduce to you:

We all have had this experience. In the winter, some plastic products will harden. Why?

Plastic is a polymer compound obtained by polymerization of polyaddition or polycondensation reaction using a monomer as a raw material. The combination of molecules and molecules is very tight and not easy to move. For example, polyethylene (PE) is one of plastics and is a high molecular organic compound which is polymerized from ethylene and is classified into two types of low molecular weight and high molecular weight.

Low molecular weight, generally liquid, colorless, odorless, insoluble in water, density 0.92 g / cm3, can be used as lubricants and coatings; high molecular weight is generally solid, milky white, thermoplastic, hand feels waxy The density is between 0.92 and 0.96 g/cm3. It is corrosion resistant and has good insulation properties. High-density polyethylene has the characteristics of rigidity, hardness and mechanical strength. It can be used as a container, a pipe, or a high-frequency electrical insulating material for radar and television.

It is insoluble in water and has little water absorption. It is only slightly soluble in some chemical solvents such as toluene and acetic acid at temperatures above 70 °C. However, the particulate polyethylene can be melted or solidified with a change in temperature between 15 ° C and 40 ° C. When the temperature is raised, it melts and absorbs heat; when the temperature is lowered, it solidifies and releases heat. The plastic products used in life are soft because plasticizers are added during manufacturing.

These plasticizers, like lubricating oils, weaken the gravitational pull between the molecules of the polymer, allowing the molecules and molecules to move, thus making the plastic soft. Some plasticizers have poor cold resistance, and the lubricating effect is weakened at low temperatures in winter. The molecules in the plastic are tightly combined and cannot be flexibly rotated, resulting in hardening of the plastic. The temperature will pick up, the plasticizer will restore lubrication, and the plastic will still be as soft as ever.

In addition, the plasticizer has a certain volatility. When the plastic product is used for a long time, the plasticizer slowly evaporates, the lubricating effect decreases, and the plastic hardens. With the deepening and development of scientific research, the application requirements are also expanding, cold-resistant and low-temperature resistant, and weakly volatile plasticizers are also emerging. Plastic products with these characteristics of plasticizers are used, and they remain soft in winter.

Through the introduction of the above-mentioned Hubei health care product plastic bottle manufacturer, I believe that everyone has already understood the reasons for the hardening of plastic products in winter.