Acrylic acid is one of the key downstream products of propylene. The annual consumption of propylene accounts for about 4% of the total consumption of propylene in China. Acrylic acid is mainly used for the synthesis of various acrylate, followed by the production of acrylate. Common acrylate mainly includes methyl acrylate (MA), ethyl acrylate (EA), butyl acrylate (BA) and 2-ethylhexyl acrylate (2-EHA), etc. Acrylate is mainly used as polymeric monomer in the production of coatings and adhesives. It is also widely used in the fields of printing ink, textile and plastic auxiliaries. Acrylate (mainly sodium salt) homopolymerization or copolymers with different composition and degree of polymerization with water absorption, water retention, cohesion and dispersion, thickening and bonding properties, are widely used in sanitary materials, rural water, water treatment, oil, paint, printing ink, textile, printing and dyeing, paper making, leather making, food processing, etc.
In the future, the following new downstream materials of acrylic acid can be focused on:
Compared with the traditional solvent-based coatings, waterborne coatings have the advantages of low price, safe use, saving resources and energy, reducing environmental pollution and public hazards, so it has become the main direction of the current development of coatings industry. Waterborne acrylate resin (acrylate emulsion) is the fastest developing and most variety of non – pollution products in coating resin. Acrylate emulsion commonly used in waterborne coatings include hydroxyl acrylate emulsion, self-crosslinking acrylate emulsion, epoxy modified acrylate emulsion, alkyd resin modified acrylate emulsion, fluorinated acrylate emulsion and other products.
In the future, the research focus of acrylate emulsion is to develop high performance acrylate emulsion products, to replace solvent based products in a wider field, and to develop functional modified acrylate emulsion. At present, the research on acrylate emulsion used in coatings is developing vigorously at home and abroad, and the performance of emulsion is gradually improved. With the introduction of environmental protection laws and regulations in various countries and the general trend of energy conservation, the application of acrylate emulsion in coatings will have a broader development prospect.
Radiation curing (also known as UV curing) technology to special acrylate as the main raw materials, using ultraviolet light or electron beam as the initiator to make acrylate polymerization. Compared with the conventional polymerization method, this method does not use chemical initiator, polymerization at room temperature, no heating, saving initiator, energy saving, and some specific process requirements must adopt this polymerization method.
Special acrylate (monomer) according to the structure can be divided into single functional acrylate (including high alkyl, special groups, special structure) and multi-functional acrylate (including bifunctional, trifunctional, etc.). At present, more than 100 kinds of special acrylate have been synthesized in the world, and the annual output is about 200,000 tons, which is only about 5% of the output of general acrylate. However, due to its structure, it can contain ester group and amino group, hydroxyl group, cyanide group, sulfonic acid group, epoxy group, furan group, etc., so that it is given various functions.
Superabsorbent (Super Absorbent Polymer, or SAP) is a loose network structure low crosslinking degree of hydrophilic Polymer compound, is insoluble in water, and difficult to soluble in organic solvent, the absorption ability of water hundreds of even thousands of times its own weight, and water absorption rate, water retention performance is good, even if the pressure is also difficult to separate the water. Because SAP has the characteristics of good water absorption, moderate price and good safety, it has been widely used in infant diapers, women’s hygiene products, adult incontinence products and other disposable hygiene products. Sodium acrylate is generally used as cross-linked polymeric monomer in these fields.
ACM is an elastomer obtained by copolymerization of acrylate as the main monomer. Its main chain is a saturated carbon chain and its side group is a polar ester group. ACM has excellent heat resistance, aging resistance, oil resistance, ozone resistance, ultraviolet resistance and other properties, mechanical properties and processing properties are better than fluorine rubber and silicone rubber, heat resistance, aging resistance and oil resistance is better than nitrile butadiene rubber.
ACM is widely used in a variety of high temperature and oil resistant environments, and has become a sealing material focused on the development and promotion of the automobile industry in recent years, especially for high temperature resistant oil seals, crankshafts, valve stems, cylinder gaskets, hydraulic oil pipelines, etc. At present.
ASA and ABS are of a similar structure as the ASA is not containing unsaturated double bond of acrylic ester rubber replaced ABS containing unsaturated double bond polybutadiene rubber, therefore, can resist ultraviolet radiation caused by the degradation and aging, fade, also can resist high temperature oxidation and the process from the atmosphere or discoloration caused by decomposition with strong security, thus greatly improve the material of anti-aging and corrosion resistance performance.
The main application fields of ASA resin include synthetic resin tiles, electrical and electronic shell materials, automotive exterior materials, outdoor building materials, etc .
Ethylene-acrylic acid copolymer has good low temperature performance and softness, excellent resistance to bending cracking and environmental stress cracking, and has great elasticity. Ethylene-acrylic acid copolymer can replace ethylene – vinyl acetate copolymer (EVA) in some applications. At present, the annual consumption of EVA in China is about 1.5 million tons, and the import volume is about 1 million tons. Compared with EVA, EAA has higher thermal stability and is a non-corrosive product, which can adapt to a wider range of processing conditions.
The main applications of ethylene-acrylic copolymer include high voltage cable shielding, hoses, packaging materials, adhesives, cryogenic sealing rings, household appliance components, and can also be blended with olefin polymers or engineering plastics to improve their low softenness, environmental stress cracking resistance and impact resistance. Ethylene-acrylate (EEA) is the most widely used copolymer of ethylene-acrylate.
EEA is a soft thermoplastic with lower crystallinity than PE. Generally containing ethyl acrylate (EA) 5-20%. The density and softness of copolymer increased with the increase of EA content. EEA has good low temperature performance and softness, good thermal stability in processing, good compatibility with packing, good resistance to bending cracking and environmental stress cracking, with greater elasticity. The crosslinking of EEA with organic peroxides can improve the heat resistance, creep resistance and solvent resistance.
Chloroethylene – acrylate copolymer is a kind of copolymer resin with excellent comprehensive properties. Compared with ordinary PVC resin, vinyl chloride – acrylate copolymer has good impact performance, easy processing and other excellent characteristics. According to the different copolymerization methods and copolymer structures of vinyl chloride and acrylic ester, the copolymer of vinyl chloride and acrylic acid system produced in China mainly includes the random copolymer of vinyl chloride and acrylic ester and the graft copolymer of vinyl chloride and acrylic ester.
With the increase of the content of acrylate in the copolymer, the porosity of the copolymer particles, the amount of plasticizer absorption, the glass transition temperature decreased, and the impact strength increased
The acrylate latex (ACR) with core-shell structure was prepared by grafting copolymer of vinyl chloride and acrylic ester, which was directly added to the suspension polymerization system of vinyl chloride for in-situ polymerization to prepare impact resistant PVC resin. In addition, ACR impact modifier can also be added in the process of PVC processing to produce copolymer materials. The representative product is acrylic copolymerized polyvinyl chloride (AGR), which is mainly used as water supply pipe. It has the reputation of “plastic steel pipe”, and has excellent impact resistance, compression resistance and seismic performance.