Vinyl chloride-2-ethylhexyl acrylate copolymers

Vinyl chloride/2-ethylhexyl acrylate copolymers were prepared by suspension copolymerization (1). 

Vinyl chloride [228] was polymerized and copolymerized in suspension at low temperature in the presence of a peroxide, a reducing agent, and a copper accelerator. Thus, the vinyl chloride-2-ethylhexyl acrylate copolymer was prepared in 100% yield by using the recipe given in Table 19. 

TabI 19 Typical Recipe Suspension Polymerization of Vinyl Chloride-2-ethylhexyl Acrylate Copolymer ... 

Whilst vinyl acetate is reluctant to copolymerise it is in fact usually used today in copolymers. Two of particular interest to the plastics industry are ethylene-vinyl acetate (Chapter 11) and vinyl chloride-vinyl acetate copolymers (Chapter 12). In surface coatings internal plasticisation to bring the Tg to below ambient temperatures and thus facilitate film forming is achieved by the use of ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate and dialkyl maleates and fumarates. 

Ethylhexyl acrylate manufacture represented about 15 percent of domestic consumption of the alcohol. The acrylate is the longest chain acrylate ester produced by esterification of acrylic acid. The monomer is used in acrylic copolymers for pressure sensitive adhesives, PVC impact modifiers, and as a comonomer with vinyl acetate and vinyl chloride in latexes for paints and textiles. Growth over the next 5 years is estimated at 6 percent per year. 

Copolymers of acrylonitrile and methyl methacrylate (115) and terpolymers of acrylonitrile, styrene, and methyl methacrylate (116,117) are used as barrier polymers. Acrylonitrile copolymers and multipolymers containing butyl acrylate (118—121), ethyl acrylate (122), 2-ethylhexyl acrylate (118,121,123,124), hydroxyethyl acrylate (120), vinyl acetate (119,125), vinyl ethers (125,126), and vinylidene chloride (121,122,127—129) are also used in barrier films, laminates, and coatings. Environmentally degradable polymers useful in packaging are prepared from polymerization of acrylonitrile with styrene and methyl vinyl ketone (130). Table 5 gives the structures, formulas, and CAS Registry Numbers for several comonomers of acrylonitrile. 

Unexpectedly, when films were cast from these poly (vinyl chloride-g-2-ethylhexyl acrylate/acrylonitrile) solutions, they were crystal clear with very low haze values. Table IV lists some of the physical properties of these poly (vinyl chloride-g-2-ethylhexyl acrylate/acrylonitrile) cast films values for a solution blend of the acrylic copolymer and PVC are also included. While tensile strengths of the 1.0/1.5 and 1.0/4.0 acrylic copolymer/PVC-graft/blend films were about 80-90% that of the homopolymer PVC film, they were significantly higher than that of the blend polymer. Furthermore, the crescent tear strengths were higher than those of the blend and the PVC film. Most importantly, the haze values of the graft blend films were much improved over that of the blend polymer, and they more nearly approached that of the homopolymer PVC. 

The miscibility between several (meth)acrylate polymers and phenoxy (PHE) has been reported.[155,156] PEMA was noted to be partially miscible and PBMA to be phase separated in PHE blends. [155] An investigation of the effect of PMMA s tacticity on the phase behavior of PMMA/PHE blends showed aPMMA, sPMMA and iPMMA to all exhibit miscibility with PHE. [156] The miscibility of PMMA with a vinylidene chloride-acrylonitrile (20 wt% AN) copolymer was shown to be a function of the PMMA tacticity (aPMMA and iPMMA miscible with the copolymer and sPMMA immiscible). [157] Hsu et fl/.[158] reported the effect of tacticity of PMMA on the miscibility with PVAc. This study showed a limited effect of tacticity and solvent choice on the phase behavior of PMMA/PVAc blends and all blends were analyzed as being immiscible based on the observation of two Tgs. Modest areas of miscibility were established for MA, EA, nBA, and 2-ethylhexyl acrylate based acrylate-acrylic acid in the respective copolymers. No miscible combinations were found for MMA-AA or acrylate-MAA copolymers with vinyl acetateethylene (VAE) or PVAc. 

If gaseous monomers such as ethylene or vinyl chloride are used, the production processes involve polymerisation at high pressures and the polymers formed are commonly referred to as pressure polymers , e.g. copolymers of VA/E or terpolymers of VA/E/VC or VA/E/2-EHA (2-ethylhexyl acrylate). Other non-gaseous monomers may be polymerised together to form polymers in low pressure systems and these polymers are commonly referred to as conventional polymers or atmospheric polymers , e.g. VA homopolymers, Ac polymers of methylmethacrylate. Furthermore, the use of other functional monomeric units to give the polymer specific application properties, such as cross linking in cured textile fabric applications (e.g. V-methylol acrylamide, acrylamide and many others), are often employed and these polymers are commonly referred to as speciality polymers . Common to all polymerisation reactions the processes are usually carried out in a batch-wise system, but continuous processes can also be employed. 

Copolymers of 2-ethylhexyl acrylate, vinyl acetate, and MA, in the range 59-64 35-40 1, have been produced in isopropyl acetate or dichloromethane solvents.Formulation of the materials with epoxy plasticizers, solution applied and cured 3 min at 275°F on poly (vinyl chloride) gave excellent pressure-sensitive adhesive films. The small amount of anhydride lowered both shrinkage and improved the cohesion of the applied films. A version of the same theme, i.e., solution copolymerization of octyl acrylate, ethyl acrylate, vinyl acetate, and MA (70 10 20 7.5) also provides useful pressure-sensitive... 

Copolymerization is an important way to produce properties that are not possible with homopolymers. For example, the homopolymer of vinylidene chloride is highly crystalline, and though it has excellent moisture and oxygen barrier properties, it does not produces very strong film or fiber. Copolymerization with 15 percent vinyl chloride disrupts the regular structure of the homopolymer to produce a stronger, clearer, more flexible material. The copolymer retains much of the barrier properties of the homopolymer and finds wide use for food packaging and filament. Other commercial copolymers include styrene-acrylonitrile, discussed above vinylidene fluoride-hexafluoropropylene, a heat- and oil-resistant elastomer styrene-butadiene rubber ethylene-vinyl acetate hot melt adhesive and 2-ethylhexyl acrylate-vinyl acetate-acrylic acid pressure-sensitive adhesives. 

HMX HMX HMX HMX HMX HMX HMX HMX HMX HMX HMX HMX HNS NTO NTO/HMX NTO/HMX NTO/HMX PETN PETN PETN PETN PETN PETN PETN PETN PETN PETN RDX RDX RDX RDX RDX RDX RDX RDX RDX RDX RDX RDX RDX TATB/HMX Cariflex (thermoplastic elastomer) Hydroxy-terminated polybutadiene (polyurethane) Hydroxy-terminated polyester Kraton (block copolymer of styrene and ethylene-butylene) Nylon (polyamide) Polyester resin-styrene Polyethylene Polyurethane Poly(vinyl) alcohol Poly(vinyl) butyral resin Teflon (polytetrafluoroethylene) Viton (fluoroelastomer) Teflon (polytetrafluoroethylene) Cariflex (block copolymer of butadiene-styrene) Cariflex (block copolymer of butadiene-styrene) Estane (polyester polyurethane copolymer) Hytemp (thermoplastic elastomer) Butyl rubber with acetyl tributylcitrate Epoxy resin-diethylenetriamine Kraton (block copolymer of styrene and ethylene-butylene) Latex with bis-(2-ethylhexyl adipate) Nylon (polyamide) Polyester and styrene copolymer Poly(ethyl acrylate) with dibutyl phthalate Silicone rubber Viton (fluoroelastomer) Teflon (polytetrafluoroethylene) Epoxy ether Exon (polychlorotrifluoroethylene/vinylidine chloride) Hydroxy-terminated polybutadiene (polyurethane) Kel-F (polychlorotrifluoroethylene) Nylon (polyamide) Nylon and aluminium Nitro-fluoroalkyl epoxides Polyacrylate and paraffin Polyamide resin Polyisobutylene/Teflon (polytetrafluoroethylene) Polyester Polystyrene Teflon (polytetrafluoroethylene) Kraton (block copolymer of styrene and ethylene-butylene)... 

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