Acrylics, polymer manufacture

Hughes, J., Armitage, Y.C., and Symes, K.C. 1998. Application of whole cell rhodococcal biocatalysts in acrylic polymer manufacture. Antonie van l euwenhoek, 74 107-18. 

The polymeric products can be made to vary widely in physical properties through controlled variation in the ratios of monomers employed in thek preparation, cross-linking, and control of molecular weight. They share common quaHties of high resistance to chemical and environmental attack, excellent clarity, and attractive strength properties (see Acrylic ester polymers). In addition to acryHc acid itself, methyl, ethyl, butyl, isobutyl, and 2-ethylhexyl acrylates are manufactured on a large scale and are available in better than 98—99% purity (4). They usually contain 10—200 ppm of hydroquinone monomethyl ether as polymerization inhibitor. 

Despite these early successes in the commercialization of acrylic polymers, no acrylic PSAs were manufactured on a larger scale until many years later. One of the primary reasons for the initial commercial failure of the acrylic PSAs was their lack of cohesive strength. Unlike the higher Tg, plastic-like polymers obtained from monomers like methylmethacrylate, polymers synthesized from alkyl acrylates typically formed sticky, cold-flowing materials with little if any utility. 

For acrylate polymers with higher levels of carboxylic acids, THF can be modified by the addition of acids such as acetic, phosphoric, or trifluoroacetic. Levels as high as 10% acetic acid are considered acceptable by most manufacturers for their styrene/DVB columns. If such a modified mobile phase is used, it may need to be premixed rather than generated using a dynamic mixing HPLC pump because on-line mixing often leads to much noisier baselines, particularly when using a refractive index detector. 

Latex acrylic polymers, 22 41-43 Latex agglutination immunoassays, 14 141 Latex-based paper coatings, 1<8 124-125 Latex manufacturing equipment, 14 720, 721... 

Supercritical carbon dioxide has been used as a dispersing medium for the manufacture and processing of polymeric materials. The process allows for the synthesis of high molar mass acrylic polymers in the form of micrometer-sized particles with a narrow size distribution. This procedure represents an environmentally responsible alternative to aqueous and organic dispersing media for heterogeneous dispersion polymerizations (Fox, 1994). 

Advances came quickly. Chemists designed special acrylic polymers that could be used in the manufacture of leak-proof tape to wrap around undersea cables. Or blended with rubber to produce a mortar that swelled on contact with water, providing a tight seal. This was used in the construction of the Chunnel, the artery that connects England and France beneath the waters of the English Channel. You sure wouldn t want any water seeping through those walls. Super slurpers have also proven themselves useful in the little pads you sometimes... 

Potential health and safety problems of acrylic polymers occur in their manufacture. During manufacture, considerable care is exercised to reduce the potential for violent polymerizations and to reduce exposure to flammable and potentially toxic monomers and solvents. 

PVC can be blended with numerous other polymers to give it better processability and impact resistance. For the manufacture of food contact materials the following polymerizates and/or polymer mixtures from polymers manufactured from the above mentioned starting materials can be used Chlorinated polyolefins blends of styrene and graft copolymers and mixtures of polystyrene with polymerisate blends butadiene-acrylonitrile-copolymer blends (hard rubber) blends of ethylene and propylene, butylene, vinyl ester, and unsaturated aliphatic acids as well as salts and esters plasticizerfrec blends of methacrylic acid esters and acrylic acid esters with monofunctional saturated alcohols (Ci-C18) as well as blends of the esters of methacrylic acid butadiene and styrene as well as polymer blends of acrylic acid butyl ester and vinylpyrrolidone polyurethane manufactured from 1,6-hexamethylene diisocyanate, 1.4-butandiol and aliphatic polyesters from adipic acid and glycols. 

The Manufacture of Acrylic Polymers, CM-107, Rohm and Haas Co., Philadelphia, Pa. 

Several other polymers such as polyurethanes, alkyds, acrylics, polyesters, silicones, etc. can be hybridised to improve the performance or to obtain desired end-results. The growth of hybrid polymer technology is giving rise to considerable improvements, and many hybrid systems have been introduced to the market. Most of the work reported in this field is for coatings, but at the same time it is useful for other products used in the construction industry. Research is under way by many polymer manufacturers and universities, and innovations are continuously being reported. In this chapter we shall be dealing with those combinations which are useful, or may be useful, for the construction industry. 

The range of monomers available and copolymeiization in varying compositional blends makes the number of possible polymer variants immense. Acrylic and styrene-acrylic copolymers are the most widely used polymers in paints and other coatings. According to Lesko " acrylic polymers account for 30% of commercial emulsion polymers. Other polymers commonly used in film forming latices are polychloroprene and poly(vinyl acetate). Polystyrene-cobutadiene latices are mixed with cement and sand to form rubberized cement, as well as being used as additives in textiles and paper industries, and in the manufacture of foam rubber. 

Special methods of incorporation in ceramics manufacture, the presence of sodium ions on the alumina surface could inhibit the formation of covalent bonding with acrylate polymers, the surface adsorption can be regulated by adjusting pH ... 

Both polymer manufacturers and polymer converters will continue to investigate new monomers, plasticizers, and additives. Greater use of olefins, maleates, and acrylates as comonomers with vinyl chloride will occur. Regulations and restrictions on solvent use will continue to encourage use of resins that have greater solubility in order to achieve higher solids and/or to tolerate poorer solvents. 

The design and manufacture of acrylate polymers represents a versatile technology for polymers used in a wide variety of applications. The ratios of such commonly used acrylate monomers as butyl acrylate... 

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