Plastic products have always played an important role in China's packaging industry due to its excellent product characteristics and excellent cost performance, but the environmental problems it brings have always been the public's attention. With the development of science and technology, green plastic products have been continuously developed and introduced.
Plastic products have always played an important role in China's packaging industry due to its product characteristics and excellent cost performance. {TodayHot} But the environmental problems it brings have always been the public's attention. With the development of science and technology, green plastic products have been continuously developed and introduced into the market.
At the beginning of the new year, the reporter noticed that the water-soluble PVA film in these products seems to be more favored by many parties. At the beginning of the year, the project “Development of water-soluble PVA film at room temperature in Yongan City” in Fujian Province has attracted many attentions in the industry and is about to be held soon. At the Central Investment and Trade Expo, there are several related investment projects in the six central provinces. What are the advantages of water-soluble PVA films, and why they stand out in the same category and win the attention of many parties? The reporter recently visited the experts and related technicians of water-soluble PVA film.
Green PVA film Water-soluble PVA film is a novel green packaging material. The main raw material is polyvinyl alcohol with low alcoholysis. It utilizes the film-forming property, water solubility and degradability of polyvinyl alcohol. Additives such as surfactants, plasticizers, {HotTag} anti-adhesives, etc. Water-soluble film products are green packaging materials, and are recognized by the environmental protection departments in Europe, America, Japan and other countries.
At present, biological oxygen consumption (BOD) and chemical oxygen demand (COD) are mainly used as indicators of environmental protection at home and abroad. The Japanese department has determined that the biological oxygen consumption (BOD) of polyvinyl alcohol is much smaller than that of starch. American Air Products Company can measure the amount of BOD below 1% of the total amount of BOD after biodegrading Airworth PVA products for 5 days. . Bio-tests have shown that polyvinyl alcohol is neither toxic nor prevents the growth and reproduction of microorganisms, and has no effect on wastewater treatment and environmental sanitation.
The microbial decomposition test of the relevant departments also showed that the polyvinyl alcohol can be almost completely decomposed, and the COD is lowered very low. As far as the degradation mechanism is concerned, polyvinyl alcohol has two degradation characteristics of water and organism. Firstly, it is dissolved in water to form a gel solution which penetrates into the soil, which increases the stickiness, gas permeability and water retention of the soil, and is particularly suitable for sand reforming. The PVA in the soil can be decomposed by the bacteria isolated from the soil, a single cell. A symbiotic system composed of at least two bacteria can degrade polyvinyl alcohol: one is an active bacteria of polyvinyl alcohol, and the other is a microorganism which produces a substance required for a PVA active bacteria. The oxidation reaction enzyme of the secondary alcohol catalyzes the polyvinyl alcohol, and then the hydrolase cuts off the oxidized PVA main chain, further degrading, and finally degrading to CO2 and H2O.
Classification, PVA films can be divided into fast dissolving films, medium soluble films and poorly soluble films. These three types of products are widely used in daily life, among which fast-dissolving films can be used in disposable packaging bags such as garment embroidery substrates, agricultural seed bags, herbicide packaging bags, cleaning products, chemical product packaging and hospital washing bags. Medium-soluble films are mainly used in wigs, food and cosmetic packaging bags; and insoluble films are mainly used in high-grade textiles, plastic outer packaging bags, packaging cushion air cushions, books, paper protective films. It can be said that the water-soluble plastic packaging film is one of the green materials that have been successfully developed at home and abroad in recent years.
Product Features of PVA Films Although environmental protection has long been the mainstream of today's society, in order to be recognized by the market, the products themselves must have characteristics superior to those of similar products. PVA films offer significant advantages in many ways.
Compared to other film products, the physical properties of PVA film make it exceptionally competitive. PVA film is superior to other films in terms of gloss and transparency. Compared with commonly used cellophane (PT) and PVC film, its reflectivity is higher than 20%, and the light transmittance is more than 50%. In terms of barrier properties, PVA film has strong permeability to moisture and ammonia. Its moisture permeability is similar to that of cellophane. It can ensure that no fog will be produced when packaging hot and wet materials. At the same time, it is suitable for oxygen and nitrogen. Hydrogen, helium, argon and carbon dioxide have superior barrier properties. Under dry conditions, its oxygen permeability coefficient is lower in various resin films. The barrier rate to oxygen in normal pressure environment is about common polyethylene. 1000 times the film and 300 times the polypropylene film, this allows the PVA film to maintain the composition of the packaged product and its own odor. Excellent aroma retention and anti-sublimation properties make PVA film packaging not only maintain the fragrance of the package, but also prevent the package from being affected by external odor.
Because PVA film has good toughness and high tensile strength, its tear strength ranks first among all kinds of films. Its biaxial tensile strength is superior, its resistance to twist is 10 times that of other films, and its weather resistance is good, which guarantees a better product. Long service life. Unlike many plastic films, which have strong chargeability, PVA film has almost no static electricity. In the process of packaging products with PVA film, it will not cause plasticity reduction or electrostatic dusting due to static electricity. At the same time, it has excellent performance. Oil resistance (vegetable oil, animal oil, mineral oil), fat resistance, organic solvent resistance and carbohydrate characteristics, these two characteristics make PVA film has a wider application prospect in the packaging of many special products.
With these excellent physical properties, PVA film has an unparalleled advantage in product processing. It has low affinity for highly hydrophobic plastics and good release (peeling) properties for various organic materials with low polarity. It can be plated with aluminum under vacuum of 1.33×10Pa～266×10Pa, and its products are in 30°C water. After immersion for 24 hours, the coating will not peel off.
Moreover, the printing performance of PV A film is superior to other films, and it has excellent water color and ink printing property, which is an incomparable advantage that the existing plastic film can only be printed by ink, and can be used for water transfer printing such as glass, ceramics, Color printing of electrical enclosures, etc.; at the same time, PVA film is highly polar, and can be printed without EDM, which also makes it widely used in special printing industries such as water transfer film substrates.
China's PVA film technology is currently in the process of manufacturing PVA film at home and abroad, and now there are mainly solution flow method (wet method) and extrusion blown film method (dry method). Both processes are born out of traditional plastic film production. Because PVA is a water-filling material, the film forming process conditions are different from thermoplastics. Therefore, the above two processes are directly applied to the production of PVA film. There are still many technical problems, and some economic problems are also generated, such as the quality is not easy to control. Low efficiency, high energy consumption, large floor space, and high equipment investment. Therefore, research and improvement of these two types of process technology and equipment, making it more suitable for PVA film production, is the focus of research and development in the industry at home and abroad.
These two methods have different characteristics due to the large difference in process flow. According to experts, the solution casting process is relatively simple, but the product quality is not easy to control, the filming rate is low, the energy consumption is high, and the equipment investment is large; while the extrusion blown film method is in terms of product quality and production efficiency. There is a significant improvement in the extension method. However, the experts also pointed out that the PVA in the extrusion blown film method must be modified. After the pre-granulation, the amount of the process and the auxiliary materials are increased. The resin and the film are repeatedly heated in the whole production process, and must be kept in the film. 15%～35% water content, complicated process, high technical difficulty and high energy consumption; and film forming, stretching and shaping are carried out at the same time, the molecular chain is difficult to move, the degree of orientation is poor, and the obtained film is not high in strength and is not sufficient. It exerts the inherent characteristics of PVA resin. At present, the research and application of domestic solution rotting method and extrusion blown film method have entered the application stage, and some products have also been exported to overseas.
At the same time, domestic research units have continuously improved and innovated PVA film technology in combination with actual production conditions, creating good economic and social values. For example, at the 9th Asia-Pacific International Plastics and Rubber Industry Exhibition in August last year, the water-soluble high-barrier PVA granulation and its blown film process were realized. Based on domestic equipment, PVA dry granulation and blowing were realized. The membrane retains the excellent properties of water solubility, barrier properties and biodegradability of PVA; and, compared with wet processing technology, it has the advantages of simple process, low energy consumption, high efficiency and low investment. This technology not only fills the blank of China's PVA dry extrusion processing technology, but also has strong market competitiveness. Compared with international similar products, the cost is only 1/10 to 1/5 of them.
Prospects for the development of domestic PVA film
At present, in Europe, America and Japan, water-soluble polyvinyl alcohol film has been widely used in the packaging of various products, such as pesticides, fertilizers, pigments, dyes, detergents, water treatment agents, mineral additives, detergents, concrete additives, photography. Chemical reagents and chemical reagents for horticultural care. Japan, the United States, France and other countries have produced and sold such products in large quantities. Some well-known multinational companies, such as Bayer, Henkel, Shell, and AgrEva, have begun to use water-soluble films to package their products. The development of water-soluble PVA film in China is still in its infancy, but the domestic PVA film market has great potential and business opportunities.
China has a large population and a huge market for packaging products. One of the market rules of the packaging industry is that in developed regions, the greater the demand for products, the higher the performance requirements of the products. According to conservative estimates, the annual demand for packaging film in Beijing alone is as high as one million tons. Especially in recent years, with the improvement of people's living standards, they have higher requirements for their own health, and the demand for green environmental protection products is increasing. PVA film has good performance, wide application and green environmental protection, which can fully meet the needs of the market. In recent years, the Chinese government has vigorously called on the people to follow the path of sustainable development, and the policy has tilted toward the green environmental protection industry, which has strongly supported the promotion and development of water-soluble PVA packaging films. In particular, with China's accession to the WTO and the Beijing 2008 Olympic Games approaching, the domestic environmental protection requirements for packaging are increasing. PVA films with excellent performance and biodegradability will surely receive more attention. PVA flexible packaging film Research, development and application in China will also have a broader market prospect. At the same time, China is still a major producer of PVA, with a production volume of one-third of the world, which makes the development of domestic PVA film even more powerful.
Patented full biodegradable film and PVA bag, all products are made by casting equipment, It is different from traditional blow molding products, all blow molding products are non full biodegradable. We can produce pva films and bags in all transparent and various colors.
For more PVA film and bags products please visit us:
http://www.joyful-printing.net/pva-bag/
http://www.joyful-printing.com/pva-bag/
The factory is located in the chuangxin industrial Park of Leiyang City, Hunan Province. 2 hours high-speed railway journey from Shenzhen. With cheap manpower and development costs, so we could offer good products with cheap price to our guests.
There are several advanced PVA water-soluble film production lines, various packaging bags and shopping bag production lines in our factory. We have developed PVA films of various temperatures. Among them, PVA high-temperature film technology is the world's leading film technology, and there is a strong R&D team and management team in our factory. We are a new materials technology company specializing in the research, production and sale of water-soluble films (PVA-polyvinyl alcohol film).
PVA water-soluble film has excellent barrier properties, water solubility and environmental friendliness. It is one of the most successful green materials in recent years. It has been widely recognized by environmental authorities and users at home and abroad, and is increasingly used in packaging, textile embroidery and water transfer printing.
For example: pesticides, fertilizers, dyes, detergents, water treatment agents, mineral additives, detergents, chemical reagents for garden care, etc., can also be used as rapeseed, plant seed bags, clothing bags, food and hospital washing bags, industrial The packaging of various products such as supplies and electronic products can also be used for textile embroidery padding materials, water transfer printing, and film stripping. At the same time, the company successfully developed packaging bags and supermarket shopping bags for various application scenarios this year. Customized bags and shopping bags of various specifications.
The factorey specializes in product quality, technology improvement and product innovation, and is committed to providing customers with products and services that are satisfactory.