Ester Copolymers

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). 

Many synthetic latices exist (7,8) (see Elastomers, synthetic). They contain butadiene and styrene copolymers (elastomeric), styrene—butadiene copolymers (resinous), butadiene and acrylonitrile copolymers, butadiene with styrene and acrylonitrile, chloroprene copolymers, methacrylate and acrylate ester copolymers, vinyl acetate copolymers, vinyl and vinyUdene chloride copolymers, ethylene copolymers, fluorinated copolymers, acrylamide copolymers, styrene—acrolein copolymers, and pyrrole and pyrrole copolymers. Many of these latices also have carboxylated versions. 

Copolymers Containing Ethylene 277 Table 11.12 Typical properties of three olefin-ester copolymers... 

Standard-grade PSAs are usually made from styrene-butadiene rubber (SBR), natural rubber, or blends thereof in solution. In addition to rubbers, polyacrylates, polymethylacrylates, polyfvinyl ethers), polychloroprene, and polyisobutenes are often components of the system ([198], pp. 25-39). These are often modified with phenolic resins, or resins based on rosin esters, coumarones, or hydrocarbons. Phenolic resins improve temperature resistance, solvent resistance, and cohesive strength of PSA ([196], pp. 276-278). Antioxidants and tackifiers are also essential components. Sometimes the tackifier will be a lower molecular weight component of the high polymer system. The phenolic resins may be standard resoles, alkyl phenolics, or terpene-phenolic systems ([198], pp. 25-39 and 80-81). Pressure-sensitive dispersions are normally comprised of special acrylic ester copolymers with resin modifiers. The high polymer base used determines adhesive and cohesive properties of the PSA. 

PSS columns for aqueous separations PSS HEMA Bio and the further improved PSS SUPREMA columns are based on methacrylic ester copolymer technology and exhibit very good stability while maintaining high efficiency. 

Synthesis of Segmented Siloxane-Ester Copolymers with (Si—O—C) Linkages 1851... 

W. Ritter, C. Meyer, W. Zollner, C. P. Herold, and S. von Tapavicza. Use of selected acrylic and/or methacrylic acid ester copolymers as flow enhancers in paraffin-rich crude oil and crude oil fraction (II) (Verwendung ausgewahlter Copolymeren der Acryl- und/oder Methacrylsaureester als FlieBverbesserer in paraffinreichen Erdolen und Erdolfraktionen [II]). Patent EP 332002,1989. 

One-to-one random copolymers of acrylic acid with either hydroxyethyl acrylate (a hydrogel model) or methyl acrylate failed to protect insulin from release under gastric conditions (Figure 6). In the case of the hydrogel, the expected swelling due to exposure to water occurred, releasing insulin. The behavior of the ester copolymer led to the prediction that there should be no more than about four carbon atoms per carboxylic acid group in a repeat unit of the polymers. We have not been able to disprove this hypothesis thus far. 

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. 

The isoprene units in the copolymer impart the ability to crosslink the product. Polystyrene is far too rigid to be used as an elastomer but styrene copolymers with 1,3-butadiene (SBR rubber) are quite flexible and rubbery. Polyethylene is a crystalline plastic while ethylene-propylene copolymers and terpolymers of ethylene, propylene and diene (e.g., dicyclopentadiene, hexa-1,4-diene, 2-ethylidenenorborn-5-ene) are elastomers (EPR and EPDM rubbers). Nitrile or NBR rubber is a copolymer of acrylonitrile and 1,3-butadiene. Vinylidene fluoride-chlorotrifluoroethylene and olefin-acrylic ester copolymers and 1,3-butadiene-styrene-vinyl pyridine terpolymer are examples of specialty elastomers. 

Ethylene-acid and ethylene-ester copolymers (EBA, EGMA, EMAH, EEA, EAA. ..)... 

Table 2 contains the characteristics of the amic ester-aryl ether copolymers including coblock type, composition, and intrinsic viscosity. Three series of copolymers were prepared in which the aryl ether phenylquinoxaline [44], aryl ether benzoxazole [47], or aryl ether ether ketone oligomers [57-59] were co-re-acted with various compositions of ODA and PMDA diethyl ester diacyl chloride samples (2a-k). The aryl ether compositions varied from approximately 20 to 50 wt% (denoted 2a-d) so as to vary the structure of the microphase-separated morphology of the copolymer. The composition of aryl ether coblock in the copolymers, as determined by NMR, was similar to that calculated from the charge of the aryl ether coblock (Table 2). The viscosity measurements, also shown in Table 2, were high and comparable to that of a high molecular weight poly(amic ethyl ester) homopolymer. In some cases, a chloroform solvent rinse was required to remove aryl ether homopolymer contamination. It should also be pointed out that both the powder and solution forms of the poly(amic ethyl ester) copolymers are stable and do not undergo transamidization reactions or viscosity loss with time, unlike their poly(amic acid) analogs.

These comprise components A to C, the amount of component B being 5 to 50 pbw per 100 pbw of A (based on solid content) and the amount of C being 50 to 350 pbw per 100 pbw of A (based on solid content). A is an emulsion of ethylene-vinyl ester copolymer, which is composed of 5 to 35 wt.% of ethylene and 95 to 65 wt.% of vinyl ester, and has a Tg of -25 to -I-15C and a toluene-insoluble part of 30 wt.% or more. B is a thermal expansive hollow microbead and C is an inorganic filler. The emulsion has superior mechanical strength, crack resistance, water resistance, alkali resistance, blocking resistance, foaming property, embossing property and superior flame resistance and can be used for flameproof foam sheet for wallpaper. 

A foamable composition nsefnl for rotational moulding is described, which advantageonsly inclndes an ethylene vinyl ester copolymer as an additive. The additive beneficially has a higher melt index than the base resin of the composition. 

The discussion to this point has involved copolymers in which both repeating units have the same functional group. A second catagory of copolymer involves different functional groups in the two repeat units, for example, an amide-ester copolymer such as... 

ASA acrylonitrile styrene acrylic ester copolymer blend... 

Copolymers of ethylene vinylacetate are the most commonly utilized fuel wax crystal modifiers. Other compounds such as vinyl acetate-fumarate copolymers, styrene-ester copolymers, diester-alphaolefin copolymers, as well as alkyl carbamate compounds are effective wax crystal modifiers. These compounds differ in both chemical structure and in the extent of performance provided. See FIGURES 6-7 and 6-8. 

Controlled delivery of theophylline from methacrylic ester copolymers and 117... 

C. Thermally Stable Adhesives a. Polyvinyl alcohol/ester copolymers... 

The complexation and sorption process on an ester copolymer were studied by factorial designs (pH, shaking time and reagent concentration)... 

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