PE is the synthetic resin with the largest output in the world and the plastic packaging material with the largest consumption. Polyethylene products are divided into three types: low density, medium density and high density. Among them, high-density polyethylene (HDPE) has a high degree of crystallinity, and its hardness, air tightness, mechanical strength, and chemical resistance are all good, so it is widely used in blow molding to make hollow containers such as bottles. Taking advantage of the good heat sealing performance of PE, the containers made of various composite materials can be used to hold various beverages such as lemon juice and fruit juice.
The rheology of PET in the molten state is better, and the influence of pressure on viscosity is greater than that of temperature. Therefore, the fluidity of the melt is mainly changed from pressure. 1. Processing of plastics Because the PET macromolecules contain lipid groups and have a certain degree of hydrophilicity, the pellets are more sensitive to water at high temperatures. When the water content exceeds the limit, the molecular weight of PET decreases during processing, and the products are colored, become brittle. Therefore, the material must be dried before processing, and the drying temperature is 150°C for more than 4 hours, generally 170°C for 3-4 hours. The air shot method can be used to check whether the material is completely dry. Generally, the proportion of recycled materials should not exceed 25%, and the recycled materials should be thoroughly dried.
Yuyao Hongda Sprayer Co.,Ltd.,established in 1996,located in Yuyao,a historical city which is close to Shanghai and Ningbo international ports with a superior geographical position.
Over the past 20 years, Hongda company has been devoted to the production of cleaning products,personal care products,hand pump sprayer,cosmetics and other packaging products. Also the company has formed a complete industrial chain of R&D, precision mold, automatic equipment manufacturing,injection molding and automatic assembly.
Hongda company has cooperated with domestic and overseas well-known brands to provide them with high quality products, excellent services, complete solutions and get win win on both sides as always.
Hongda based on reality, relying on a fine management to process continuous innovation, to pursuit of high quality,and to promote the sustainable development of the company.