1 Introduction
As a supporting industry of national economy, the development speed and quality of powder coating are closely related to the international and domestic economic environment, and the introduction and implementation of relevant policies and regulations will also seriously affect the development direction of powder coating industry. In order to control the serious haze problem, both central and local governments have introduced relevant policies to limit the development of solvent-based coatings while environmentally friendly powder coatings are promoted, which is undoubtedly a good news for the environmentally friendly powder coating industry. However, the inherent defects of powder coating products need to be solved, or else good opportunities will be missed. The technical progress of powder coating relies heavily on the development of raw material resin, curing agent and additives. Polyester resin is the raw material of powder coating industry in China, and the technical investment of polyester resin for powder coating has increased in recent years, and the research and development work is relatively active. Research direction mainly includes: the selection of new polyol, polyacid and low-toxic non-toxic catalyst; polymer polyester material molecular structure redesign; the application of new processes; the development of polyester resins for powder coatings applicable to near-infrared curing and polyester production process esterification water and other by-products of recycling research.
From the patents in recent years can be found, the current research on polyester is mainly focused on special decorative powder coating with polyester resin, but also coil powder coating with polyester resin, heat-sensitive base material powder coating with polyester resin, crystalline polyester resin, anti-corrosion powder coating with polyester resin, but no patent reports for the synthesis of powder coating with polyester resin catalyst-related aspects of research.
Developing green catalysts or minimizing the use of non-green catalysts can make our process and product application green. Finding or developing an efficient and environmentally friendly catalyst can also greatly improve our production efficiency and bring direct economic benefits to the company.
Catalysts have always been an important element in the development of polyester technology, and scholars at home and abroad have conducted in-depth research on the mechanism of polycondensation reaction, catalytic mechanism of metal catalysts, and types of catalysts. And never stop the exploration of new catalysts. However, the main research areas and the problems targeted to solve are concentrated in PET polyester industry.
In response to the requirements of environmental protection, the research on catalysts for polyester resins for powder coatings has become more important and urgent.
2 Policies and Regulations for Powder Coating Polyester Resins
In today’s global economic integration, smooth access to the global market is becoming more and more important to the success of an enterprise, and Chinese coating enterprises must take the international road while improving themselves. As the main raw material of powder coatings, polyester resin also needs to comply with the corresponding laws and regulations.
2.1 Chinese industry standard
In order to promote industry self-regulation, standardize the market and promote the healthy development of powder coatings, GB/T 27808-2011 saturated polyester resin for thermosetting powder coatings has been developed.
2.2 RoHS Directive
Powder coatings exported to EU countries must comply with RoHS directive. The “EU Eco-label” has been recognized by EU consumers.
The EU Parliament and the EU Council adopted the RoHS Directive in January 2003, the full name is TheRestriction of the use of certain Hazardous substances in Electrical andElectronic Equipment, that is, the Restriction of the use of certain hazardous substances in electrical and electronic equipment. The RoHS Directive, also known as Directive 2002/95/EC, was later supplemented to specify the large limit values of six hazardous substances. The new RoHS in Europe is currently the CE/RoHS certification directive 2011/65/EU.
The Directive requires that electrical and electronic products placed on the EU market must not contain six hazardous substances, including lead, mercury, tin, hexavalent chromium, polybrominated diphenyl ethers and polybrominated biphenyls.
The purpose of the RoHS Directive is to prohibit the sale and use of products containing certain hazardous substances in the EU market. Powder coating is closely related to electronic equipment because powder coating is used as a decorative or functional material in refrigerators, washing machines, microwave ovens, air conditioners, notebooks and other electronic and electrical equipment. All countries in the world adopt RoHS standard according to IEC62321 standard, European CE-ROHS is mandatory, China ROHS is voluntary certification, and there are corresponding international certification bodies in China.
2.3 REACH regulation
REACH regulation was introduced to protect human health and the environment, to make enterprises take the responsibility of chemical risk management, to maintain and improve the competitiveness of the EU chemical industry, to prevent the fragmentation of the internal market, to improve transparency, to disclose all chemical information and management regulations, to comply with WTO principles and to promote international integration. Enterprises have to pre-register or register their products to sell to Europe and the U.S. The 161 substances of very high concern (SVHC) specified in REACH, polyester resins for powder coatings also have to be given for testing of 161 substances.
2.4 EU Toy Directive 2009/48/EC
The EU is an important export destination for toys in China, and domestic toy enterprises generally believe that the requirements for toys exported to the EU are high. This mainly stems from the EU’s very strict and detailed safety requirements. Focused on the EU toy safety directive, June 30, 2009, the EU “Official Journal” published a new version of the EU Toy Safety Directive (Directive 2009/48/EC), the directive takes into account technological developments and new toy safety issues. The definitions are clearer, with the Directive amending the definition of a toy to “a product designed or intended for use (whether or not solely) by children under 14 years of age for play.” This definition indicates that for those products that are certainly not designed for use in play by children under the age of 14, but are likely to be used by children for play, they must meet the safety performance requirements set out in the new Directive. The directive increases the restrictions on migratory elements to 19; lists 55 kinds of banned fragrances and 11 kinds of fragrances that require warning labels; for the first time, the ban on carcinogenic, mutagenic, fertility (CMR) substances. In addition, the Directive also specifies that toy products should meet the requirements of the EU General Chemical Regulation.
From Table 1 can clearly see the total content of organic tin has a clear limit, the content required between 0.2-12PPm, and the current synthetic powder coatings with polyester resin catalysts are mostly monobutyltin oxide. There is also a limit for the total tin content, but the allowed range is significantly wider than that of organotin, therefore, environmentally friendly inorganic tin catalysts are available for polyester researchers to consider.
2.5 European Toy Standard EN71
The European Committee for Standardization issued the EN71 series of standards in 1978, after continuous updates and modifications as well as additions, has now formed a series of 11 parts of the standard. The third part of the standard specifies the migration of certain elements. EN71-3:2000Migration of certain elements.
2.6 Other countries toy regulations
2.6.1 U.S. Toy Regulations
Toys exported to the United States need to pass the ASTMF963 standard test, and need to pay attention to the CPSC16CER requirements and changes, and need to pay close attention to the U.S. local state regulations requirements, some local regulations in the United States than the relevant provisions of the country.
As early as 1976, the U.S. published the toy safety standard PC72-76, in 1996, the American Society for Testing and Materials (ASTM) PC72-76 standard was revised and published as ASTMF963 standard “Consumer Product Safety Specifications for Toys”, the standard fully refers to the safety parameters of EN71 and IS08142.
The U.S. Consumer Product Safety Commission (CPSC) developed the U.S. Federal Consumer Product Safety Regulation Part 16 (16CER) for the U.S. national mandatory regulations. This part is mainly for children’s products mechanical, physical properties, flammability, chemical properties and safety labeling requirements.
2.6.2 International Toy Standard ISO8124
The international toy standard ISO 8124 is drafted by the International Toy Standardization Organization on the European toy standard EN-71, the American toy standard ASTMF963 and other national standards, in which the third part provides for the transfer of certain elements.
In addition, countries like Japan and Canada have their own toy standards, which are not listed here.
2.7 IKEA Standard
As the world’s largest furniture and home furnishings business IKEA, based on national or international regulations and consideration of health and human environment, certain compounds and chemicals
