Acrylonitrile-butadiene-styrene modification

R. Qi, J. Qian, and C. Zhou, Modification of acrylonitrile-butadiene-styrene terpolymer by grafting with maleic anhydride in the melt. I. Preparation and characterization, J. Appl. Polym. Sci., 90(5) 1249-1254, October 2003. 

J. Abenojar, R. Torregrosa-Coque, M.A. Martinez, and J.M. Martin-Martinez, Surface modifications of polycarbonate (PC) and acrylonitrile butadiene styrene (ABS) copolymer by treatment with atmospheric plasma, Surf. Coat. Technol, 203(16) 2173-2180, May 2009. 

Acrylonitrile-Butadiene-Styrene (ABS). ABS plastics are derived from acrylonitrile, butadiene, and styrene. ABS materials have a good balance of physical properties. There are many ABS modifications and many blends of ABS with other thermoplastics that can affect adhesion properties. ABS resin can be bonded to itself and to other materials with adhesives, by solvent cementing, or by thermal welding. 

Acrylonitrile-butadiene-styrene (ABS) and acrylonitrile-styrene-acry- late (ASA) are rubber-toughened plastics based upon the styrene-acrylonitrile (SAN) copolymer matrix. The combination of the stiffness and toughness exhibited by these materials has made them increasingly attractive in engineering applications, and the activity of the patent literature testifies to a continuing interest in improving properties through modifications of structure. The aim of this paper is to discuss a quantitative approach to structure-property relationships in ABS and ASA polymers. 

Modifications. A recoverable and reusable catalyst has been prepared from an acrylonitrile-butadiene-styrene polymer and OSO4. ... 

The wide variety of applications of anaerobic adhesives and sealants is made possible by the modifications that make the viscosity appropriate to the application. An application that requires penetration into close-fitting parts should have very low viscosity, while a produet used with large, loose-fitting parts should have a high viscosity. A styrene aerylate eopolymer could be used to increase the viscosity [59]. Polymethacrylates, eellulose esters, butadiene-styrene eopolymers, acrylonitrile-butadiene-styrene copolymers, poly(vinyl ehloride), copolymers of vinyl chloride and vinyl acetate, poly(vinyl aeetate), eellulose ethers, polyesters, polyurethanes, and other thermoplastic resins have also been used to eontrol the flow eharacteristics of anaerobic sealants [60]. The flow eharaeteristies of anaerobic formulations can also be controlled by the addition of fumed siliea and other solid additives whieh can impart thixotropic properties [61]. 

Patented or commercial polymer blends are in most cases multiphase, compatibilized systems. In the old but still popular blends of polyvinyl chloride or polycarbonate with acrylonitrile-butadiene-styrene copolymer, PVC/ABS or PC/ABS, the styrene-acrylonitrile copolymer, SAN, ascertains adequate compatibilization in the systems. Note that ABS went through a series of process and composition modifications to enhance performance in blends. 

Traugott and co-workers [41] place the emphasis on aspects of PP, acrylonitrile-butadiene-styrene (ABS) and polycarbonate (PC) blends with ABS or impaa modifiers. Material development benefits from a host of recent technical advancements such as catalysis, reaction engineering, impact modification and compatibilisation. Some examples of these are fourth generation Ziegler-Natta and metallocene polyolefin catalysts, highly efficient solution processes (PP and ABS) and copolymer modifiers. 

Acrylonitrile is also commonly found in impact modifiers, such as the acrylonitrile-butadiene-styrene (ABS) type, produced by emulsion polymerisation. Polybutadiene seed latex particles are grafted onto styrene and acrylonitrile in a seeded emulsion polymerisation process. As the styrene-acrylonitrile copolymer shell forms, polybutadiene domains are spontaneously separated within. The resulting impact modifier particles are subsequently compounded with polystyrene to product high impact polystyrene (HIPS). The impact modification properties of the latex particles may be optimised through varying the butadiene content, the particle size and structure, and the shell molecular weight. A basic formulation for an ABS impact modifier is given in Table 6. 

The core of organic composite latex particles can be varied along with the desired properties. The most important parameters of the polymer in the core are the Tg, the molar mass, the crosslink density, and the type of (co)polymer. Composite latex particles used for impact modification consist of a rubbery core and a glassy shell that is miscible or can react with the matrix. Examples of such types of polymers are the very important acrylonitrile-butadiene-styrene (ABS) composite polymer and also the methyl methacrylate-butadiene-styrene transparent composite polymer for the impact modification PVC. For coating applications the latex particles often consist... 

Acryhc stmctural adhesives have been modified by elastomers in order to obtain a phase-separated, toughened system. A significant contribution in this technology has been made in which acryhc adhesives were modified by the addition of chlorosulfonated polyethylene to obtain a phase-separated stmctural adhesive (11). Such adhesives also contain methyl methacrylate, glacial methacrylic acid, and cross-linkers such as ethylene glycol dimethacrylate [97-90-5]. The polymerization initiation system, which includes cumene hydroperoxide, N,1S7-dimethyl- -toluidine, and saccharin, can be apphed to the adherend surface as a primer, or it can be formulated as the second part of a two-part adhesive. Modification of cyanoacrylates using elastomers has also been attempted copolymers of acrylonitrile, butadiene, and styrene ethylene copolymers with methylacrylate or copolymers of methacrylates with butadiene and styrene have been used. However, because of the extreme reactivity of the monomer, modification of cyanoacrylate adhesives is very difficult and material purity is essential in order to be able to modify the cyanoacrylate without causing premature reaction. 

The polymers described above have been chemically pure, although physically helerodisperse. It is oflen possible lo combine two or more of these monomers in the same molecule to form a copolymer. This process produces still further modification of molecular properties and, in turn, modification of the physical properties of file product. Many commercial polymers are copolymers because of the blending of properties achieved in this way. For example, one of the important new polymers of the past ten years has been the family of copolymers of acrylonitrile, butadiene and styrene, commonly called ABS resins. The production of these materials has grown rapidly in a short period of time because of their combination of dimensional stability and high impact resistance. These properties are related to the impact resistance of acrylonitrile-butadiene rubber and the dimensional stability of polystyrene, which are joined in the same molecule. 

Acrylic copolymers (i.e., core-shell impact modifiers with a shell of PMMA and a core of butyl acrylate elastomer) have been developed mainly for impact modification of PVC for outdoor applications. Butadiene-styrene copolymers are used exclusively for PVC, PC or styrene-acrylonitrile (SAN). Thermoplastic elastomers in the form of styrenic copolymers, e.g., SBS, are used preferably for styrenics and PA. Polyolefins, like EVA, are used for impact modification of technical polymers. 

Acrylonitrile-butadiene rubber, NBR, styrene-aciylonitrile rubber, SAN, ethylene-vinyl acetate copolymer, EVA, and acrylic copolymers are helpful modifications of polyvinylchloride that change its processing characteristics and elastomeric properties. Blending with these copolymers helps to reduce the requirement for low molecular weight plasticizers. Ethylene-vinyl acetate copolymer plays a role of high molecular weight plasticizer in production of vinyl hose. This reduces the amount of DOP used in flexible hose applications. Ethylene copolymer is used plasticize PVC that reduces gel. "" Phthalate plasticizers can be eliminated from water based adhesives because of utilization of vinyl acetate ethylene copolymer as a high molecular plasticizer/modifier. " ... 

When chlorinated polyether is used instead of butadiene, a copolymer called acrylonitrile-chlorinated polyethylene styrene (ACS) is produced. This copolymer has improved flame resistance and weatherability. [See also acrylonitrile-chlorinated styrene (ACS) teropolymer polyethylene styrene (ACS) terpolymer.] Acrylic styrene acrylonitrile (ASA) is produced by grafting an acrylic ester elastomer onto the styreneacrylonitrile segment. This results in better outdoor weathering. ASA is used in products such as gutters, mailboxes, shutters, and outdoor furniture. (See also acrylic styrene acrylonitrile.) Modifications are also available that enhance adhesion of electroplated coating to the ABS plastic. ABS is the most widely used material for electroplated plastic parts. 

The butadiene-styrene rubber (SBR), or butadiene-acrylonitrile rubber (NBR) and elastomeric graft copolymers were found particularly valuable for impact modification of PP. The PP alloys (with 5-20 wt.% of an elastomer) were reported to have advantageous properties for blow molding of bottles free from brittleness and stress cracking. Blends with natural rubber (NR) require sulfur-curing [4]. Blending with NBR dramatically increased the modulus, but the material was brittle [5]. 

Rubber vulcanization crosslinking was an early chemical modification method. Block and graft methods are also widely used in polymer modification. One of the successful examples of a block copolymer is a thermoplastic elastomer. It is a new material that can be processed like plastic and has elasticity like rubber. Among graft copolymers, the most widely used one is the acrylonitrile butadiene and styrene copolymer... 

Representative diene-based polymers include natural rubber (NR), polyisoprene (PIP), PBD, styrene—butadiene rubber (SBR), and acrylonitrile-butadiene rubber (NBR), which together compose a key class of polymers widely used in the rubber industry. These unsaturated polyolefins are ideal polymers for chemical modifications owing to the availability of parent materials with a diverse range of molecular weights and suitable catalytic transformations of the double bonds in the polymer chain. The chemical modifications of diene-based polymers can be catalytic or noncatalytic. The C=C bonds of diene-based polymers can be transformed to saturated C—C and C—H bonds (hydrogenation), carbonyls (hydrofbrmylation and hydrocarboxylation), epoxides (epoxidation), C—Si bonds (hydrosilylation), C—Ar bonds (hydroarylation), C—B bonds (hydroboration), and C—halogen bonds (hydrohalogenation). ... 

Acrylonitrile-styrene-butadiene polymers (ABS) These are complexes of blends and copolymers of excellent toughness. Some recent modifications show a degree of transparency. 

Terpolymerization, the simultaneous polymerization of three monomers, has become increasingly important from the commercial viewpoint. The improvements that are obtained by copolymerizing styrene with acrylonitrile or butadiene have been mentioned previously. The radical terpolymerization of styrene with acrylonitrile and butadiene increases even further the degree of variation in properties that can be built into the final product. Many other commercial uses of terpolymerization exist. In most of these the terpolymer has two of the monomers present in major amounts to obtain the gross properties desired, with the third monomer in a minor amount for modification of a special property. Thus the ethylene-propylene elastomers are terpolymerized with minor amounts of a diene in order to allow the product to be subsquently crosslinked. 

Polystyrene is one of the most widely used thermoplastic materials ranking behind polyolefins and PVC. Owing to their special property profile, styrene polymers are placed between commodity and speciality polymers. Since its commercial introduction in the 1930s until the present day, polystyrene has been subjected to numerous improvements. The main development directions were aimed at copolymerization of styrene with polar comonomers such as acrylonitrile, (meth)acrylates or maleic anhydride, at impact modification with different rubbers or styrene-butadiene block copolymers and at blending with other polymers such as polyphenylene ether (PPE) or polyolefins. 

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