Acrylate-type copolymer

TEXAPRET C is the aqueous, highly viscous solution of a non-ionic, acrylate-type copolymer. It has a weakly alkaline reaction and a solids content of approx. 16%. 

Application The high-pressure Lupotech A autoclave reactor process is used to produce low-density polyethylene (LDPE) homopolymers, EVA and various acrylic type copolymers. Single-train capacity of up tol 25,000 tpy can be provided. 

It is worthwhile to make an additional point on the polymer-solvent interaction parameter Xi3- In reality it may be a function of the reaction temperature thus, isooctane, being a strong precipitating media for polystyrene at room temperature, may represent a better solvent at 70-80°C. Consequently, the start of phase separation and the resulting porous structure may well depend on the reaction conditions [267]. In the case of acrylic-type copolymers, the influence of temperature on the Flory-Hu ns parameter was found to be even more important [268]. 

A process based on saponification of ethylene—acrylate ester copolymers has been practiced commercially in Japan (29). The saponification naturally produces fully neutralized polymer, and it is then necessary to acidify in order to obtain a pardy neutralized, melt-processible product. Technology is described to convert the sodium ionomer produced by this process to the zinc type by soaking pellets in zinc acetate solution, followed by drying (29). 

Siloxane containing polyester, poly(alkylene oxide) and polystyrene type copolymers have been used to improve the heat resistance, lubricity and flow properties of epoxy resin powder coatings 43). Thermally stable polyester-polysiloxane segmented copolymers have been shown to improve the flow, antifriction properties and scratch resistance of acrylic based auto repair lacquers 408). Organohydroxy-terminated siloxanes are also effective internal mold release agents in polyurethane reaction injection molding processes 409). 

We can incorporate short chain branches into polymers by copolymerizing two or more comonomers. When we apply this method to addition copolymers, the branch is derived from a monomer that contains a terminal vinyl group that can be incorporated into the growing chain. The most common family of this type is the linear low density polyethylenes, which incorporate 1-butene, 1-hexene, or 1-octene to yield ethyl, butyl, or hexyl branches, respectively. Other common examples include ethylene-vinyl acetate and ethylene-acrylic acid copolymers. Figure 5.10 shows examples of these branches. 

We make polyethylene resins using two basic types of chain growth reaction free radical polymerization and coordination catalysis. We use free radical polymerization to make low density polyethylene, ethylene-vinyl ester copolymers, and the ethylene-acrylic acid copolymer precursors for ethylene ionomers. We employ coordination catalysts to make high density polyethylene, linear low density polyethylene, and very low density polyethylene. 

Not all modified starches are suitable for removal by aqueous dissolution alone. Such modifications of natural starches are carried out to reduce solution viscosity, to improve adhesion and ostensibly to enhance aqueous solubility. Commercial brands vary [169], however, from readily soluble types to those of limited solubility. Indeed, some may be as difficult to dissolve as potato starch if they have been overdried. It is thus very important to be sure of the properties of any modified starch present. If there are any doubts about aqueous dissolution, desizing should be carried out by enzymatic or oxidative treatment. Even if the size polymer is sufficiently soluble, it is important to ensure that the washing-off range is adequate. Whilst the above comments relate to modified starches, other size polymers such as poly(vinyl acetate/alcohol) and acrylic acid copolymers vary from brand to brand with regard to ease of dissolution. 

From dimeric to oligomeric sodium acrylate having a molecular weight of 500 was easily biodegraded. However, it seems that the specific microbes utilizing this polyvinyl-type copolymers as a sole carbon source are relatively scarce in the environment, and the biodegradability of these types of copolymers differ according to... 

Tsitsilianis et al. [14] also reached the conclusion, from size exclusion chromatography measurements, that AnBn type copolymers, where A is PS and B is poly(ferf-butyl acrylate), are more expanded than the corresponding homostars, due to the increased density of two different kinds of segments which leads... 

The selection and chemical modification of the current generation of chemically and physically robust stationary phases with narrower particle and pore size distributions has been based on the developmental effort that has occurred over the past 20 years. Initially chemically modified, deformable polymeric gels were used, such as the crosslinked agaroses, dextrans, or acrylate-based copolymers, but more recently various classes of highly refined type I and type II silicas and other ceramic materials, or new classes of controlled porosity polymeric organic materials have found increasing application. 

Vinyl lacquers are used mainly where a high degree of chemical resistance is required these lacquers are based on vinyl chlorides and vinyl acetates. Acrylic lacquers are based on methyl methacrylate and methyl acrylate polymers and copolymers. Other esters of acrylic and methacrylic acid also may be used to make nonconvertible film formers. Judicious selection of these acrylic acid or methacrylic acid esters allows one to produce film formers with specifically designed properties such as hardness, flexibility, gloss, durability, heat, and chemical resistance. Acrylic lacquers, however, are not noted for their water resistance. The principal uses of acrylic-type lacquers are fluorescent and metallic paints, car refinish applications, clear lacquers and sealers for metals, and protective coatings for aircraft components and for vacuum-deposited metals, as well as uses in pigmented coatings for cabinets and appliances. 

The high pressure polymerization of ethylene can be slightly modified for the copolymerization of ethylene with vinyl- and acrylic-type monomers such as vinyl acetate, vinyl chloride, acrylonitrile, or acrylic esters. Some of these copolymers of ethylene and vinyl acetate or maleic anhydride are already available and have found various applications in plastics, coatings, and adhesives. Copolymers of ethylene and vinyl chloride and of ethylene and acrylonitrile appear particularly interesting because of the low cost of monomers and the properties of the copolymers. Although their synthesis has been disclosed in a number of patents their larger scale production is still in a state of development. 

Eastacryl30D, Kollicoat MAE 30 D, and KollicoatMAE 30 DP are also aqueous dispersions of the anionic copolymer based on methacrylic acid and ethyl acrylate. The copolymer also corresponds to USPNF 23 methacrylic acid copolymer. Type C. The ratio of free-carboxyl groups to ester groups is 1 1. Films prepared from the copolymers dissolve above pH... 

Nitroxides have been used to prepare numerous block copolymers. Initially, using the TEMPO moiety, only styrene-based monomers could be incorporated into copolymers, but with the use of new nitroxides like DEPN and BPPN, the list has expanded to include acrylate-type monomers, as well as dienes, something that previously could only be accomplished through ionic mechanisms. Unfortunately, chain extension of either St or diene-based macroinitiator with an acry-... 

Acrylate-type rubbers Acrylate-butadiene rubbers Acrylic rubbers Butadiene rubbers Butadiene acrylonitrile copolymers (more than 50 percent butadiene) Butadiene-styrene copolymers (more than 50 percent butadiene)... 

In any case, for such compounds, silica gel-based column material should be avoided as much as possible. Fortunately, various type of non-silica gel-based C-18 and other reverse-phase columns are now widely available. They include matrices such as polystyrenedivinylbenzene and hydroxyethyl meth-acrylate/dimethylacrylate copolymers with various functional groups. Recovery rates are generally much better on these polymeric materials, and are accompanied by a much longer column life. These alternative supports are also more tolerant to extreme pH and high concentrations of buffers such as ammonium acetate. 

The PVC blends are usually compatibilized by addition of an acrylic copolymer, viz. ABS, MABS, MBS, or a core-shell-type copolymer (consisting of ABS-core and grafted on it acrylo-... 

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