Polymers polystyrene acrylonitrile

In the case of poly(vinyl chloride) plastics, the FWA is mixed dry with the PVC powder before processing or dissolved in the plasticising agent (see Vinyl polymers). Polystyrene, acrylonitrile—butadiene—styrene (ABS), and polyolefin granulates are powdered with FWA prior to extmsion (2,78) (see... 

Styrene is an important monomer or comonomer in the manufacture of a number of polymers polystyrene, acrylonitrile/butadiene/styrene, styrene/acrylonitrile, etc. There are two main processes for the manufacture of styrene. In one process styrene is made a coproduct with propylene oxide ... 

Fishbein L. 1984. Toxicity of the components of styrene polymers Polystyrene, acrylonitrile-butadiene-styrene (ABS) and styrene-butadiene-rubber (SBR). Reactants and additives. In Jarvisalo J, Pfaffli P, Vainio H, eds. Industrial hazards of plastics and synthetic elastomers. New York, NY AlanR. Liss, Inc., 239-262. 

Styrene is a commercially important monomer that is used extensively in the manufacture of polystyrene resins and in co-polymers with acrylonitrile and 1,3-butadiene (reinforced plastics). Exposure to styrene occurs due to intake of food that has been in contact with styrene-containing polymers. lARC has determined that styrene is possibly carcinogenic to humans. There is no restriction on using styrene within the European Union (i.e., there is no SML). 

STYRENE. Styrene, CgH5CH=CH2, is the simplest and by far the most important member of a series of aromatic monomers. Also known commercially as styrene monomer (SM). styrene is produced in large quantities for polymerization. It is a versatile monomer extensively used for the manufacture of plastics, including crystalline polystyrene, rubber-modified impact polystyrene, expandable polystyrene, acrylonitrile-butadiene-styrene copolymer (ABS), styrene-acrylonitrile resins (SAN), styrene-butadiene latex, styrene-butadiene rubber (SBR). and unsaturated polyester resins. See also Acrylonitrile Polymers. 

Styrene is at the centre of an important industry, with a value of some 66 billion euros. The styrene production capacity is ca. 20 Mt/a worldwide. Most is obtained by ethylbenzene dehydrogenation and all the production is used for the synthesis of polymers (polystyrene, styrene-acrylonitrile, styrene-butadiene) used as plastics and rubbers in the manufacture of household products packaging, tubes, tires, and endless other applications (see also Chapter 7). 

BAKELITE RMD 4511 CEVIAN HL DIALUX ESTYRENE AS KOSTIL LITAC LURAN LUSTRAN POLYSTYRENE-ACRYLONITRILE 2-PROPENENITRILE POLYMER with ETHENYLBENZENE... 

Craze formation is a dominant mechanism in the toughening of glassy polymers by elastomers in polyblends. Examples are high-impact polystyrene (HIPS), impact poly(vinyl chloride), and ABS (acrylonitrile-butadiene-styrene) polymers. Polystyrene and styrene-acrylonitrile (SAN) copolymers fracture at strains of 10 , whereas rubber-modified grades of these polymers (e.g., HIPS and ABS) form many crazes before breaking at strains around 0.5. Rubbery particles in... 

About 65% of styrene is used to produce polystyrene. Polystyrene is used in the manufacture of many commonly used products such as toys, household and kitchen appliances, plastic drinking cups, housings for computers and electronics, foam packaging, and insulation. Polystyrene finds such widespread use because it is relatively inexpensive to produce and is easy to polymerize and copolymerize, resulting in plastics with a broad range of characteristics. In addition to polystyrene, styrene is used to produce acrylonitiile-butadiene-styrene polymer, styrene-acrylonitrile polymer, and styrene-butadiene synthetic rubber (SBR). 

Free-radical polymerization reactions have recently been studied for different monomers, for example mono and disubstituted vinyl monomers and dienes. The bulk polymerization of vinyl monomers (e.g. vinyl acetate, styrene, methyl methacrylate, and acrylonitrile) has been investigated by Amorim et al. [10]. The reactions were conducted in the presence of catalytic amounts of AIBN (or benzoyl peroxide). It was found that the rate of polymerization depends on the structure of the monomers and the power and time of microwave irradiation. In a typical experiment 10.0 mL of each monomer and 50 mg AIBN was irradiated in a domestic microwave oven for 1 to 20 min to afford the polymers polystyrene, poly(vinyl acetate), and poly(methyl methacrylate) with weight-average molecular weights 48 400, 150 200, 176700 g mol, respectively (Scheme 14.1). The experiments were performed without temperature control. 

Vu-Khanh T. Fracture behaviour of high-impact polystyrene and acrylonitrile-butadiene-styrene, Chapter 27. In Scheirs J, Priddy DB, editors. Modem Styrenic Polymers Polystyrenes and Styrenic Polymers. Hoboken (NJ) John Wiley and Sons 2003. 

Some polymers are essentially amorphous (e.g., polystyrene, acrylonitrile butadiene styrene copolymer, polycarbonate, and polymethyl methacrylate) while others are semicrystalline (e.g., polyolefins and polyamides). The former tend to have a wide melting temperature range with a comparatively high melt strength, while semicrystalline polymers tend to have a narrow melting temperature range and frequently a low melt strength. 

Like impact polystyrene, acrylonitrile-butadiene-styrene copolymers (ABS) are sensitive to oxidation caused by the unsaturation of the elastomeric component. The processes for the manufacture of ABS require the drying (at 100°C-150°C) of powdery polymers that are extremely sensitive to oxidation. Thus, antioxidants have to be added before the coagulation step, normally in emulsified form, although sometimes in solution. The primary antioxidants are frequently sued together with a synergist. Primary anti-oxidants commonly used for ABS are BHT, 2,2 -methylenebis-(4-ethyl or methyl-6-tert-hutyl-phenol), 2,2 -methylenebis-(4-methyl-6-cyclohexyl-phenol), 2,2 -methylenehis-(4-methyl-6-nonyl-phenol), octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)-propionate, and l,l,3-tris-(5-tert-hutyl-4-hydroxy-2-methylphenyl)-butane. Important synergists are tris-(nonyl-phenyl)-phosphite and dilauryl thiodipropionate. These antioxidants are either liquids or show comparatively low melting points, which is an important prerequisite for the formation of stable emulsions. 

As a measure of the level of sophistication of the industry the types of polymers consumed was as shown in figure 2. Others are mainly engineering thermoplastics (ETP), such as nylon, polyacrylates, polyacetals, polycarbonates, polyesters, and polpropylene oxide etc... These ETP s are growing at rates up to 20%. The main uses for plastic products are computer and business machine parts as well as design engineered products. The consumption of styrenic plastics (polystyrene acrylonitrile butadiene styrene - ABS) is high, relative to polyolefins, because of their demand in electric/electronic end-uses. 

Source-based names are, for example, the ones we are accustomed to seeing for polymers such as polyethylene (see Section 6.21) and polystyrene (see Section 11.17). When the name of the monomer is a single word, the polymer derived from it is generated by simply adding the prefix poly-. When the name of the monomer consists of two words, both words are enclosed in parentheses immediately following poly. Thus, polyacrylonitrile and poly(vinyl chloride) are the polymers of acrylonitrile and vinyl chloride, respectively. 

Naidu, B. V. K., MaUikarjuna, N. N., and Aminabhavi, T. M. 2004. Blend compatibility studies of polystyrene/poly(methyl methacrylate) and polystyrene-acrylonitrile by densitometry, viscometry, refractometry, ultraviolet absorbance, and fluorescence techniques at 30°C. Journal of Applied Polymer Science 94 2548-2550. 

Styrene serves as the monomer for the well-known polymer—polystyrene. It also serves as the source of many copolymers, that is polymers made from two monomers at varying compositions, such as SAN = styrene-acrylonitrile SBR = styrene-butadiene rubber (the major synthetic rubber) SBS = styrene-butadiene-styrene (a modem family of thermoplastic mbbers which are not cross-linked) and the well-known terpolymer ABS which is based on 3 monomers—acrylonitrile-butadiene-styrene. 

Synonyms Polystyrene/acrylonitrile Poly (styrene-co-acrylonitrile) 2-Propenenitrile polymer with ethenylbenzene SAN SAN copolymer... 

Plastics can be divided according to their character into amorphous and crystalline. Crystallization is never complete and the so-called crystalline polymers are virtually semicrystalline ones. Examples of amorphous plastics are polystyrene, acrylonitrile-butadiene—styrene copolymers, styrene—acrylonitrile copolymers, polymethylmethacrylate, poly(vinyl chloride), cellulose acetates, phenylene oxide-based resins, polycarbonates, etc. Amorphous polymers are characterized by their glass transition temperature, semicrystalline polymers by both melting and glass transition temperatures. 

Polymer Polyols (BP Chemicals) are dispersions of polystyrene acrylonitrile copolymer particles of 0-5-F5/im in polyether polyols sterically stabilized with non-aqueous dispersants (NAD). Use of these with the conventional urethane polyols enables elastomers of relatively high hardness, high strength and exceptionally high elongation at break to be... 

The radicalic stage of the cryolitic mechanism is also sustained by the grating and block copolymerisation reactions released, for instance those carried out on the cryolised starch solution in the presence of different polymers (polystyrene) or monomers (styrene, acrylonitrile) [1169, 1182]. 

A range of polymer blends were investigated by Kirste et al. who found that most of the systems under investigation had positive Ai values. Only blends of polystyrene-acrylonitrile copolymer with differing styrene weight fractions were found to have. >4 2 less than zero. This would lead to phase separation at a sufficiently high molecular weight in these blends. 

The microstructure observed for thick films shows fibrils, about 4-10 nm in diameter for polystyrene, in agreement with SAXS measurements on the crazes in the bulk polymer. Very thin films of polystyrene (100 nm) show modification in the craze structure as there is no plastic restraint normal to the film [397]. Deformation zones have also been studied in polycarbonate, polystyrene-acrylonitrile and other polymers [398]. Crazes in thermosets can be studied in thin films spun onto NaCl substrates which can be washed away when the film has been cured. Mass thickness measurements are difficult to make in radiation sensitive materials that is why most TEM work has been done on polystyrene and least on PMMA. After developing the techniques described above for TEM Donald and Kramer [398] applied similar methods in optical microscopy to study radiation sensitive materials and the kinetics and growth of deformation zones. Thin films were strained on grids in situ in a reflecting OM. Change of interference color, which depends on the film thickness, was a very sensitive method for observing film deformation. 

This was demonstrated for the series of polymers polystyrene (PS), poly(acrylonitrile) (PAN), poly(methyl methacrylate) (PMMA), and polyacrylic acid (PAA) using silica-coated and clean gold tips. The histograms of the pull-off forces (10) are shown in Figure 5, indicating that polymers with different functionalities can be chemically distinguished, provided that the mechanical properties are similar. 

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