Butadiene polymer

Acrylics. Acetone is converted via the intermediate acetone cyanohydrin to the monomer methyl methacrylate (MMA) [80-62-6]. The MMA is polymerized to poly(methyl methacrylate) (PMMA) to make the familiar clear acryUc sheet. PMMA is also used in mol ding and extmsion powders. Hydrolysis of acetone cyanohydrin gives methacrylic acid (MAA), a monomer which goes direcdy into acryUc latexes, carboxylated styrene—butadiene polymers, or ethylene—MAA ionomers. As part of the methacrylic stmcture, acetone is found in the following major end use products acryUc sheet mol ding resins, impact modifiers and processing aids, acryUc film, ABS and polyester resin modifiers, surface coatings, acryUc lacquers, emulsion polymers, petroleum chemicals, and various copolymers (see METHACRYLIC ACID AND DERIVATIVES METHACRYLIC POLYMERS). 

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

Several other ozonides were prepd from butadiene polymers, but it was not stated whether or not they were expl... 

Brandt [200] has extracted tri(nonylphenyl) phosphite (TNPP) from a styrene-butadiene polymer using iso-octane. Brown [211] has reported US extraction of acrylic acid monomer from polyacrylates. Ultrasonication was also shown to be a fast and efficient extraction method for organophosphate ester flame retardants and plasticisers [212]. Greenpeace [213] has recently reported the concentration of phthalate esters in 72 toys (mostly made in China) using shaking and sonication extraction methods. Extraction and analytical procedures were carefully quality controlled. QC procedures and acceptance criteria were based on USEPA method 606 for the analysis of phthalates in water samples [214]. Extraction efficiency was tested by spiking blank matrix and by standard addition to phthalate-containing samples. For removal of fatty acids from the surface of EVA pellets a lmin ultrasonic bath treatment in isopropanol is sufficient [215]. It has been noticed that the experimental ultrasonic extraction conditions are often ill defined and do not allow independent verification. 

There are various requirements for impact-modified PVC. The most demanding is for outdoor sidings and window frames, where lifetimes of 20 years are expected. Because butadiene polymers or copolymers (e.g., acrylonitrile/butadiene/styrene (ABS), methyl methacrylate/butadiene/styrene (MBS)) are susceptible to UV degradation these polymers are usually not employed instead acrylate polymers are used for these applications. 

Precipitation of the catalyst can be effected by treating the polymer solution with acid/base and/or oxidants. Poloso and Murray [95] proposed a method to recycle the nickel octanoate ((CH3(CH2)6C02)2Ni)/triethylaluminum((C2H5)3Al) catalyst from a styrene-butadiene polymer solution. The polymer solution containing the catalysts was refluxed with 4 wt.% glacial acetic acid (relative to polymer) for 4 h, followed by treatment with 1.4 wt.% anhydrous ammonia. The solution was then filtered through a diatomaceous earth. The nickel content in the polymer was decreased from 310 ppm to 5.6 ppm. 

In the styrene-butadiene polymer example, it is not physically possible to collect spectra of the pure butadiene components (cis-, trans- and 1,2-butadiene) experimentally, because they cannot be synthesized. As a result, only the CLS method that uses estimated pure component spectra basis can be used. Using the concentrations of all four major analytes for all of the calibration samples (obtained by C NMR), it was possible to estimate the pure component spectra of the four known components (see Figure 12.11). When these estimated pure component spectra are then used to estimate the concentrations of the four constituents in the samples (Equation 12.38), it is found that the RMSEE for cA-butadiene is 1.53. 

Figure 12.11 Estimates of the pure component spectra for styrene, i,2-butadiene, ds-butadiene and trans-butadiene units in styrene-butadiene polymers, obtained using the CLS method. The vertical dashed lines indicate the four wavelengths chosen by the stepwise MLR method.

C.E. Miller, B.E. Eichinger, T.W. Gurley and J.G. HermiUer, Determination of microstructure and composition in butadiene and styrene-butadiene polymers by near-infrared spectroscopy. Anal. Chem., 62, 1778-1785 (1990). 

Hydroxy-terminated polybutadiene (HTPB) is considered to be the best binder for obtaining high combustion performance, superior elongation properties at low temperatures, and superior mechanical strength properties at high temperatures. This combination of properties is difficult to achieve in double-base propellants. HTPB is characterized by terminal -OH groups on a butadiene polymer. The other type of butadiene polymer used is carboxy-terminated polybutadiene (CTPB), which is cured with an imine or an epoxy resin. It should be noted that CTPB is somewhat sensitive to humidity, which has an adverse effect on its ageing charac-... 

The butadiene polymers represent another cornerstone of macromolecular stereochemistry. Butadiene gives rise to four different types of stereoregular polymers two with 1,2 linkage and two with 1,4. The first two, isotactic (62) and syndiotactic (25), conform to the definitions given for vinyl polymers, while the latter have, for eveiy monomer unit, a disubstituted double bond that can exist in the two different, cis and trans, configurations (these terms are defined with reference to the polymer chain). If the monomer units all have the same cis or trans configuration the polymers are called cis- or trans-tactic (30 and 31). The first examples of these stereoisomers were cited in the patent literature as early as 1955-1956 (63). Structural and mechanistic studies in the field have been made by Natta, Porri, Corradini, and associates (65-68). 

Another major use of butadiene polymer is in the manufacture of HIPS. Most HIPS has about 4%i-12%i polybutadiene in it so that HIPS is mainly a PS-intense material. Here, the polybutadiene polymer is dissolved in a liquid along with styrene monomer. The polymerization process is unusual in that both a matrix composition of PS and polybutadiene is formed as well as a graft between the growing PS onto the polybutadiene is formed. The grafting provides the needed compatibility between the matrix phase and the rubber phase. The grafting is also important in determining the structure and size of rubber particles that... 

Butarez CTL Telechelic butadiene polymers Phillips Petroleum... 

Solvents Propylene L Acids Ethylene Butadiene Polymers... 

Most acrylonitrile-butadiene styrene terpolymer (ABS) is produced as a graft of SAN onto a butadiene polymer backbone. This graft copolymer may be blended with more SAN or acrylonitrile elastomer (NBR) to improve its properties. ABS is more ductile than SAN. The Tt and the heat deflection temperature of ABS vary with the composition, and ABS may have one set of values for the PBD domains and another set for the SAN matrix. The permeabilities of ABS to oxygen, nitrogen, and carbon dioxide are much less than those of hope. 

The polymer was then dried in an oven at 40°C and 60-70 mm pressure. Purified butadiene polymers and butadiene-styrene copolymers were analyzed by infrared and nmr spectroscopy(4,5,6). 

Anionic polymerization dates back at least to the early part of this century. Indeed, sodium-initiated butadiene polymers were investigated as potential synthetic rubbers many years ago. Unfortunately, the derived, high 1,2 microstructure shows a T, of about 0°C. Electron transfer initiators also were studied by Scott in 1936. 

Seed polymerization using a polystyrene latex was used by Gaschler et al. (3) to prepare aqueous styrol-butadiene polymer dispersions. 

Table 11. Eight-hour time-weighted average exposure levels of butadiene in personal breathing-zone samples at a plant producing styrene-butadiene polymer in the Netherlands, 1990-97...

Fajen, J.M. (1988) Extent of Exposure Study 1,3-Butadiene Polymer Production Industry, Cincinnati, OH, National Institute for Occupational Safety and Health... 

Matanoski, G.M. Schwartz, L. (1987) Mortality of workers in styrene-butadiene polymer production. J. occup. Med., 29, 675-680... 

Matanoski, G.M., Santos-Burgoa, C. Schwartz, L. (1990a) Mortality of a cohort of workers in the styrene-butadiene polymer manufacturing industry (1943-1982). Environ. Health Perspect.,H6, 107-117... 

S. Himei, M. Takine, and K. Akita, Blend of vinyl chloride resin and graft copolymer prepared by consecutive polymerization of monomers onto butadiene polymer, US Patent 3 288886, assigned to Kane-gafuchi Chemical Ind., November 29,1966. 

Frequently, a butadiene polymer is added as rubber component, resulting in a ABS type polymer. The ABS polymer thus obtained has an excellent impact strength even at a very low temperature. However, it exhibits a poor weather resistance and aging resistance. 

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