1 heat-resistant PET container Heat-resistant PET containers, also known as hot-fill PET containers, began their industrial production in the late 1980s and have been widely used abroad. In recent years, domestic production applications have also gradually increased, and new production routes are still being developed. Among them. The production of heat-resistant PET bottles includes heat setting technology, material blending modification method, multi-layer co-blow molding, and liquid nitrogen cooling technology. The so-called liquid nitrogen cooling technology still performs heat setting treatment by directly contacting the stretch blow-molded bottle with the high-temperature mold, but the heat-set PET bottle is not made by lowering the mold temperature but by supplying liquid nitrogen to the PET bottle. The PET bottle was quenched and the cooled PET bottle was removed from the hot mold to give a product. With the liquid nitrogen cooling technology, the temperature of the blow mold can be as high as 200°C, thus having a better treatment effect. The obtained PET bottle can withstand hot water at 100°C and high temperature filling of 110°C salad oil just because of this The current high cost of this method and the problem of process stability control have yet to be solved and there is still a certain distance from industrial production. With the high heat resistance of polyethylene naphthalate (PEN) and its good compatibility with PET resin, a certain amount of PEN resin is incorporated into the PET resin, and the PET biaxially stretch blow molded is used. Conventional equipment and processes can produce PET bottles with good heat resistance and can be used for hot filling. If they are heat-treated in the production process, they are more effective. At present, practical heat-resistant PET bottles are still generally produced using a heat-setting process route. When we develop hot-fill PET bottles, we should focus on heat-setting methods. Due to its high strength and good barrier properties, PET is widely used in packaging of Coke and other carbonated beverages, but as a commodity such as beer, which requires high oxygen barrier properties, the barrier properties of ordinary PET bottles are still insufficient. According to the literature, beer is usually required to have a shelf life of 120 days. Therefore, it is required that the oxygen permeability of beer bottles should not exceed 10-6g in 120 days, and the loss of carbon dioxide should not exceed 5%. This requirement is 2 to 5 times that of ordinary PET bottles. . In addition, beer must be disinfected after bottling, and the temperature peak can be as high as 98°C. Therefore, good heat resistance is also required. High barriers to PET bottles are mainly due to the multilayering of bottles (introducing high barrier resin layers) and the surface coating of PET bottles. With the high strength of PET, the introduction of a high barrier resin layer in the bottle wall to meet the requirements of beer packaging is an effective way to improve the barrier properties of the bottle. In 1997, the British company Bass used PET/EVOH/PET multi-layered bottle packaging for the supply of beer bottles. In 1998, France's Karlsberg Company adopted the PET/MXD6/PET multi-layered bottle packaging beer and was successfully listed. The introduction of high barrier resin layers such as EVOH and MXD6 has greatly improved the barrier properties of plastic bottles. However, the packaging of beer is still insufficient. Therefore, the development of the special metal salt in the barrier layer MXD6 (or in the copolyester) has been developed. The catalyst barrier layer, when the oxygen in the air enters this layer, under the action of the catalyst, MXD6 (or copolyester) and oxygen produce a chemical reaction to absorb oxygen and make the bottle wall play a higher barrier to oxygen. In 1998, Miller, a brewing company in the United States, had used CPT's multi-layer bottle packaging beer produced using active packaging technology and went on the market. Shanghai Zijiang Group also launched the development of multi-layer PET beer bottles, but it is said that it is currently limited to the trial of raw beer. In 1998, Carlton Company of Australia tried to sell beer filled with epoxy-coated high-barrier PET bottles. The bottle was produced by AC (Amcor Container), and the coating agent was developed by PPG. It is a two-component hardening product of epoxy compound and amine reacting m-phenylenediamine with epichlorohydrin. The outer layer of the PET bottle was applied by spraying and hardened with ultraviolet rays. TP Corporation (Tetra Pak) vapor-deposited SiOx on the inner surface of a PET bottle by a CVD plasma method and developed a barrier type PET bottle called Glaskin. It is said that the production line can produce 18,000 PET bottles with capacity up to 1L per hour. German beer company bitburger has used TP's 500ml Glaskin barrier bottle to sell beer. The caliber of this bottle is a 38mm wide mouth and is sealed by the German company Berticap's oxygen-absorbing PP. Another Swedish Spendrups company's Gulf mixed beer also uses 500mL Glaskin PET bottles. 3. PET bottle rookie PEN bottle PEN is a typical polyester polymer compound. Its molecular structure is very similar to that of PET, and can be regarded as a product in which a benzene ring in PET is substituted by a naphthalene ring. Since the naphthalene ring is more rigid than the benzene ring, PEN has higher heat resistance and mechanical strength than PET, better gas barrier properties, better chemical stability, and lower levels of many substances. Absorption. PEN has excellent molding performance and is basically the same as PET. PET bottles can be used to produce PEN bottles. The conversion of PET bottles to PEN bottles does not require huge equipment costs. PEN bottles can be directly used for high-temperature hot filling at temperatures above 80 °C without heat-setting treatment and multilayering with other heat-resistant resins. Because PEN has higher strength and higher barrier properties, it can be directly used in beer packaging without layering or surface coating. However, it must also be noted that the disadvantage of PEN's high price is very prominent. This is a big problem in its popularization and application. Because the price of PEN resin is about 4 times the price of PET resin, it only depends on the improvement of molding processing technology and it is greatly reduced. The cost of the PEN bottle is very difficult. At present, the PEN bottle can only be limited to the packaging of some products that have high performance requirements for packaging containers and are economically tolerant. The large-scale industrial production application still needs PEN resin production enterprises. The PEN bottle molding processing company's joint efforts. Pet Turf,Artificial Grass For Dog,Deodorizing Artificial Grass,Artificial Turf For Dog Parks Changshu Keyuan Eco-friendly New Materials Co.,Ltd , https://www1.ailiqingky.com
Through the heat-setting technology, the crystallinity of PET biaxially stretched blow-molded bottles can be increased, the oriented PET macromolecules can be shaped, and the heat-resistance of heat-set high-crystallinity PET biaxially stretched blow-molded bottles is significantly improved. Hot-fillable to 80°C or higher. Since the PET macromolecules are in the stretch orientation during the heat-setting process, large-sized PET spherulites may not be formed during heat-setting, so despite the increased degree of crystallinity of the heat-set PET bottles, the transparency remains high. .
Using polyarylate (u-polymer) molding properties similar to PET and high heat resistance, a multi-layer preform of PET/polyarylate/PET structure was first prepared using a multi-layered method of polyarylate and PET. , And then through the biaxial stretch blow molding, PET-based multi-layer bottles can be heated to meet the 85 °C hot filling requirements.
2. High barrier PET bottle
In recent years, ACTIS, a coating technology for plasma surface amorphous carbon developed by the company Sidel in France, used plasma-assisted acetylene to form an amorphous carbon coating with a thickness of 0.1 μm on the inner surface of PET bottles. High barrier PET bottle, the coated PET bottle is 30 times more resistant to oxygen than ordinary PET bottle, and 3 times more resistant to carbon dioxide. It is used in beer packaging and has a storage period of more than 4 months. Carbon-coated PET bottles, like ordinary PET bottles, are easily recyclable and environmentally friendly. Therefore, ACTIS technology is considered to be an ideal method for high barrier properties of PET bottles.