Starch-based plastics use chemical reaction to chemically modify starch, reduce the hydroxyl group of starch, change its original structure, thereby changing the corresponding properties of starch, and turning the original starch into thermoplastic starch.
Chinese name Starch-based plastics Industry Industrial manufacturing Fields Chemical manufacturing Applications Plastic manufacturing
table of Contents
1 Research and development background
2 Process principle
3 Development status
4 Product advantages
5 Certification System
6 Application prospects
R&D background editor
Starch is the natural polymer that is second only to cellulose in the world. It is rich in source, renewable and inexpensive. It can be used to produce starch-based plastics through modified plasticization. As an important category in bio-based materials, starch-based plastics have successfully achieved industrial production and application. Starch-based plastic is a kind of plastic product which is made of starch as the main raw material, modified and plasticized and then blended with other polymers. It is a kind of bioplastic. Starch-based bioplastics can be divided into bio-based plastics and biodegradable plastics.
Starch-based biodegradable plastics are generally blends of modified starches with biodegradable polyesters (such as PLA/PBAT/PBS/PHA/PPC, etc.), which are fully biodegradable, compostable, environmentally friendly, and suitable for waste. Composting, landfill and other treatment methods. Starch-based bio-based plastics are generally a mixture of modified starch and polyolefins (such as PP/PE/PS, etc.). Its environmental significance is to reduce the use of petrochemical resources, reduce carbon dioxide emissions, and waste is suitable for incineration. Both materials can replace traditional petroleum-based plastics and are widely used in plastic packaging materials, shock-proof materials, plastic films and plastic bags, disposable tableware, food containers, toys, and the like.
Process principle editing
Starch is a natural high molecular polymer with a large amount of hydroxyl groups in its molecule (molecular structures II and III), so the interaction between starch macromolecules is strong, which makes the original starch difficult to melt process, and is shared with other polymers. The compatibility with other polymers in the mixing process is also poor. But these hydroxyl groups can
Chemical reactions such as esterification, etherification, grafting, and crosslinking are sufficient. These chemical reactions are used to chemically modify the starch to reduce the hydroxyl group of the starch and change its original structure, thereby changing the corresponding properties of the starch and turning the original starch into a thermoplastic starch.
1. Esterification, transesterification or etherification
In order to change the hydrophilicity of the starch to hydrophobicity, the hydroxyl group on the starch molecule is esterified and transesterified with a fatty acid, a fatty acid ester or the like to form a starch ester.
2, cross-linking reaction
In order to increase the strength and heat resistance of the starch material, the starch is cross-linked with a compound having two or more functional groups (such as a polybasic acid, etc.) to cause moderate crosslinking of the starch.
3, blending and reforming copolymerization independent innovation
Most starch plastics are prepared by blending and blending starch with other polymer materials. The resulting product has limited compatibility due to poor compatibility and limited use. Starch-based plastics also copolymerize starch during the starch modification process to obtain a graft copolymer of starch and other polymers, thereby improving the compatibility of starch with other polymer materials. Through chemical modification, the starch modification was realized: the hydrophilicity was changed to hydrophobicity; the heat sensitivity was changed to temperature resistance; the hard and brittleness was changed to plasticity. This modification solves the worldwide problem of starch modification and lays a good foundation for subsequent processing.
Development status editor
Starch-based bioplastics has a history of 30 years of research and development. It is a biodegradable plastic with the longest research history, the most mature technology, the largest industrial scale and the highest market share. In the early 1980s, research and development of modified starch and degradable plastic alloy masterbatch of fully biodegradable or soluble plastics, the blending of starch and biodegradable resin was valued. Among them, the most successful is the “MaterBi” of Novamont, Italy, which is an interpenetrating network structure polymer plastic alloy composed of modified starch and modified polyvinyl alcohol. It has good processing properties, secondary processing properties and mechanics. Performance and excellent biodegradability. In addition, "Vinex" developed by Air Product & Chemical Company of the United States is a resin based on polyvinyl alcohol having a low degree of polymerization, and has water solubility, thermoplastic processability and biodegradability, and has received great attention in recent years.
In recent years, countries have generally shifted their research focus to plastics that increase starch content as much as possible, and have developed some fully degradable materials with excellent properties, and even obtained pure starch products without synthetic polymers, namely thermoplastic starch. The "Novon" biodegradable material produced by Warner-Lambert in the United States has a starch content of over 90%. The Japanese Corn Company and the Michigan Institute of Production Technology have jointly developed a high-starch material that has the advantage of high water resistance. In addition, Sumitomo Corporation of Japan and Ferrizz of Italy also announced that they have successfully studied all-starch plastics with a starch content of 90%. In the production of thermoplastic starch for the production of biodegradable plastics, research institutes such as the German Batekke Institute, the American Warner-Lambert Company and the Swiss University have made great progress. The Australian National Center for Food Processing and Packaging Science has introduced a full-starch thermoplastic with good fluidity, ductility and mold release. The product is soft, transparent, high-strength, and has a controllable degradation rate. It can be used to make agricultural film and food. Packaging film and other products.
China's starch plastics was first developed by the Institute of Applied Chemistry of the Jiangxi Academy of Sciences in the late 1980s. According to incomplete statistics, there are more than 60 institutions of higher learning, research institutes and enterprises participating in the research. China is gradually narrowing the gap with foreign developed countries in the research and development of starch-based plastics. At present, the main domestic starch-based materials and products manufacturing enterprises and the status quo are as follows: Wuhan gorgeous 40,000 tons / year, is preparing to build a production line with an annual output of 60,000 tons; Shenzhen Hongcai 15,000 tons / year; Suzhou Hanfeng 10,000 tons / year; Zhejiang Tianhe 10,000 tons / year; Zhejiang Huafa 10,000 tons / year; Shandong Bicai into 10,000 tons / year; other production enterprises also include Nanjing than Australia, Changzhou Longjun and so on.
The starch is modified and plasticized by chemical methods, and the modified starch has three major characteristics: 1. Hydrophobicity. Starch is completely hydrophobic after chemical modification, and its moisture content is <1%, which has good compatibility with other synthetic polymer materials. 2, temperature resistance. The modified starch can withstand a high temperature of 230 ° C during the thermoplastic processing without yellowing or decomposition. 3. Thermoplastic. The modified starch can be thermoplastically processed on plastic processing equipment. The starch-based plastics produced by the company are divided into two series: bio-based and bio-degradable. They are divided into blown film materials, injection plastics, sheet materials and foaming materials according to different processing techniques. They can be used in industrial and pharmaceutical applications instead of ordinary petrochemical plastics. Packaging of food, electrical appliances and other products, kitchen utensils, toys and flower planting. Thereby, a large amount of oil resources are saved, carbon dioxide emissions are reduced, garbage is harmlessly treated, and agricultural development and farmers' income are promoted, and the development of circular economy is promoted.
On July 12, 2018, Yu Long successfully developed and commercialized all-starch biodegradable materials for the first time in the world. [1]
Product advantage editing
Compared with traditional plastic products, the advantages of starch-based materials and products are as follows:
(1) Similar performance: It has the same and similar performance as traditional plastic products of the same type;
(2) Environmental protection: starch-based bio-based plastics and products have the advantages of saving petroleum resources and reducing carbon dioxide emissions; starch-based biodegradable plastics and products have the advantages of complete biodegradation, compostability and harmless disposal of garbage;
(3) Safety: Starch-based materials and products do not contain toxic and harmful substances such as plasticizers, bisphenol A and heavy metals. Food grade materials meet the relevant standards for food grade plastics at home and abroad;
(4) Production process: There is no waste discharge in the production process, which will not cause new pollution to the environment;
(5) Cost: Starch-based bio-based plastic materials and products are the same as ordinary petroleum plastic products. The cost of starch-based biodegradable materials and products is about twice that of ordinary petroleum plastics.
Certification system editing
In recent years, the environmental performance of bio-based products has been gradually recognized at home and abroad, and the application fields of bio-based materials have been greatly expanded. The bio-carbon content of bio-based materials is an important feature that distinguishes them from ordinary plastics. Bio-carbon content is defined as the percentage of biochar in organic carbon (including biochar and fossil carbon) in products. Since bio-carbon is a new carbon, it does not pollute the environment, so it has a good environmental effect. The bio-carbon content detection standards include ASTM D6866-08: Test method for determining the biological content of solid, liquid and gas samples by radiocarbon analysis and the liquid-flash counter method for bio-based content determination in Chinese GB/T29649-2013 bio-based materials. Since the contemporaneous organisms contain equal amounts of radioactive carbon, the principle of ASTM D6866 is to measure the biobased content of the sample in any state by means of this property of the organism; this method can be used to determine any biobased products and organisms. The exact percentage of biobased or renewable material contained in the base blend.
In 2009, the Belgian authoritative certification body Vincotte issued the world's first batch of OK Biobased star certification products certification, the authoritative level certification of the bio-carbon content of bio-based materials, and also provides a reliable product quality for the bio-based materials market. Third party evaluation. OK-Biobased is Belgium's environmental label for bio-based low-carbon products. Bio-based plastics manufacturers can certify their labels on product packaging or products to differentiate them from ordinary petrochemical products. It defines bio-based materials based on bio-carbon content and evaluates them as a percentage of bio-carbon content and total carbon content. The standard is ASTM D6866, which is a star-based distinction between materials and is the EU's authoritative bio-based material certification mark. The OK Biobased logo uses an asterisk to distinguish the environmental rating of the product. A certified product has a 1 star mark to prove that its product contains 20% to 40% of biochar, 2 stars are 40% to 60%, 3 stars are 60% to 80%, and 4 stars are more than 80% bio-carbon content. product. Vincotte's OK Biobased certification aims to help companies or distributors improve the market competitiveness of renewable products and guide consumers to better choose environmentally friendly products.
To encourage the development of biobased materials and products, the US Department of Agriculture has implemented a biological priority program. The program has two programs, a government procurement priority plan and a voluntary identification program for consumers. The former was in 2002 to encourage the development of bio-based products, while the latter was released in 2008. The purpose of the Bio-Priority Program is to stimulate the consumption of biomass products in the United States. Federal government agencies and their contractors prioritize the purchase of products with the highest biomass content. If the product meets the minimum standards for bio-based content in the US Department of Agriculture's bio-based product list, any factory or distributor can participate in the program, and the certificate label issued by the agency can be affixed to the product packaging.
The international certification of biodegradable plastics includes Belgian OK Compost certification, German Compostable certification, and US BPI certification.
OK Compost is a compostable certificate named "OK Compost" issued by the Belgian certification body AIB-Vincotte Group after testing according to the test standard for biodegradable materials EN13432 or ASTM D6400. OK Compost certification aims to help companies or distributors improve the market competitiveness of fully degradable products and guide consumers to better choose environmentally friendly products.
Compostable certification is the certification of biodegradable products by DIN CERTCO, a joint certification body of TUV Rheinland Group and Deutsches Institut fr Normun (DIN). The authentication ID is the “seeding” logo. Compostable certification helps buyers to select products from a wide range of suppliers and manufacturers for quality, safety and environmental protection. At the same time, products with the Compostable logo indicate that they have successfully passed the testing and evaluation of an authoritative third-party organization, which helps to enhance the customer's purchasing confidence and effectively promote product sales. And the relevant information of the holder can be inquired on the official website of DIN CERTCO to prevent abuse or forgery of the logo.
BPI is an abbreviation for Biodegradable ProductsInsitute. BPI educates producers, legislators and consumers about the scientific standards for degradable materials through an innovative compostable labeling program. At the same time, a series of procedures are in place to ensure that the relevant products meet the requirements of the standards for degradable materials.
The first batch of Chinese companies that have received OK Biobased certification in Wuhan, China, have obtained four-star bio-based product certification. At the same time, the company's biodegradable materials received OK Compost certification and Compostable certification.
Application foreground editing
With the gradual shift of consumer preference for plastic products, renewable environmentally friendly materials are heating up by the market. Affected by this, the demand for bio-based plastics market has increased. With the emphasis on bioplastics by governments, the total value of global bioplastics demand is expected to increase to $5.9 billion by 2020, which is equivalent to an average annual growth rate of 20%.
Recently, the French Parliament passed laws on energy transition and green growth. In addition to reducing the share of nuclear energy in the French energy mix, the new law also includes legislative advice related to renewable energy and plastic packaging. For example, renewable energy will increase by 40% by 2030 and carbon dioxide emissions by 40% by 2030; lightweight packaging bags for packaging fruits and vegetables will be made from bio-based materials starting January 1, 2017; In addition, plastic packaging for commercial mail will also be executed at the same time and with the same standards. The latest legislation of the French government requires that disposable tableware such as dishes and forks must be made from bio-based materials instead of petroleum-based materials.
RnR Market Research consultancy market analysts have predicted that the global demand for bio-based plastics will increase by 19% in the next four years, and its market demand will reach 950,000 tons in 2017. Europe is the world's largest consumer market for bio-based plastics. In 2012, the use of bio-based plastics in the region accounted for more than half of the global total. According to the survey report, consumers in Europe are more inclined to choose new bio-based plastic products than traditional plastics. Therefore, the region is expected to continue to lead the bio-based plastics consumption rankings. In terms of types, starch-based plastics and polylactic acid are still the most demanding bio-based plastics in the next few years, and their market consumption will account for more than 60% of the total. According to RnR Market Research, in recent years, countries have introduced restrictions on plastics, and continue to increase the supervision of the use of traditional plastics, which will help further push the demand for bio-based, especially starch-based plastics.
In 2013, the State Council promulgated the “Bio-Industry Development Plan” (hereinafter referred to as “Planning”), which states that it will accelerate the bio-based materials and bio-based
we offer 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 full transparent and various colors. and the PVA film is more smooth than the traditional blow molding products.
we also offer organic material full biodegradable film and bags with patented raw material and production Process.
For more PVA film and bags products please visit us:
http://www.joyful-printing.net/pva-bag/
http://www.joyful-printing.com/pva-bag/