Methacrylate ester, water-polymer

Difluoroethanol is prepared by the mercuric oxide cataly2ed hydrolysis of 2-bromo-l,l-difluoroethane with carboxyHc acid esters and alkaH metal hydroxides ia water (27). Its chemical reactions are similar to those of most alcohols. It can be oxidi2ed to difluoroacetic acid [381-73-7] (28) it forms alkoxides with alkaH and alkaline-earth metals (29) with alkoxides of other alcohols it forms mixed ethers such as 2,2-difluoroethyl methyl ether [461-57-4], bp 47°C, or 2,2-difluoroethyl ethyl ether [82907-09-3], bp 66°C (29). 2,2-Difluoroethyl difluoromethyl ether [32778-16-8], made from the alcohol and chlorodifluoromethane ia aqueous base, has been iavestigated as an inhalation anesthetic (30,31) as have several ethers made by addition of the alcohol to various fluoroalkenes (32,33). Methacrylate esters of the alcohol are useful as a sheathing material for polymers ia optical appHcations (34). The alcohol has also been reported to be useful as a working fluid ia heat pumps (35). The alcohol is available ia research quantities for ca 6/g (1992). 

We next investigated the dealkylation of S-b-tBM with TMSI. Unlike the reaction with S-b-MM, it required only 4 hr at room temperature to completely cleave the t-butyl ester. Work-up under acidic conditions gave S-b-MA which was virtually identical by NMR, IR, GPC, and titration with that just described above. Likewise, neutralization with KOH resulted in quantitative conversion to S-b-MA.K. Although the initially formed product of the reaction of alkyl esters with TMSI is presumably the trimethylsilyl ester (1 7 ), we were not able to isolate or characterize this copolymer. It is known that trimethysilyl methacrylate and its polymers spontaneously hydrolyze even in moist air (19). Any traces of water in the methanol used to precipitate the reaction mixture would thus preclude isolation of the intermediate trimethylsislyl ester. 

A reactor flask was charged with methacrylate ester of 9-anthracene methanol (4.2 g), 4-acetoxystyrene (13.8 g), 2,2 -azobisisobutylonitrile (0.8 g), and propyleneglycol monomethylether and then vented for 15 minutes. The reaction mixture was then heated to 70°C for 5 hours and then cooled to ambient temperature and treated with 26 wt% aqueous tetramethylammonium hydroxide (7 g). The reaction temperature was then raised to 40°C for 3 hours and then further raised to 60°C for 8 hours. The mixture was then recooled to ambient temperature and acidified to a pH of 6 using acetic acid. The polymer was precipitated in 600 ml of methanol and the solid filtered, washed with methanol and deionized water, and dried. The precipitated polymer was redissolved in propyleneglycol monomethylether (60 g) and reprecipitated in 600 ml methanol. The solid was refiltered, rewashed, dried at 40°C, and the product isolated having an Mw of 12,800 Da with an Mn of 5400 Da. 

As our first case study, dealing with pol)miers, we consider Langmuir mono-layers of poly(methacrylic ester), PMA, at the water-air interface. Data for these layers can be used to illustrate some trends and principles, laid down in sec. 3.41. In that section we discussed how the surface pressure of physisorbed polymers depends on surface concentration. In a dilute monolayer of pancakes, the surface pressure was found to be given by the ideal term plus an excluded-area contribution. We rewrite [3.4.56] in terms of the adsorbed amount r = n°/A = N°/ N A) in moles of chains per unit area... 

Because the new acrylic finishes required minimal polishing by the auto owner, the finishes were subject to water spotting. When water, or bird droppings, dried on the hood and trunk in the hot sun, permanent etches were left on the finish. Incorporation of longer ester chain methacrylates into the polymer backbone resolved this problem by rendering the coating more hydrophobic and also imparted improved flexibility without loss of hardness, when used in conjunction with special plasticizers. 

Synonyms Methacrylate copolymer Methacrylate polymer Definition Fully polymerized copolymer of methacrylic acid and an acrylic or methacrylic ester Type C may contain surfactants Properties Wh. powd., faint char, odor sol. in dll. alkali, buffer sol ns. of pFI 7, methanol, alcohol, IPA, acetone insol. in water, dll. acids vise. 50-200 cps... 

Emulsion polymerization requires free-radical polymerizable monomers which form the structure of the polymer. The major monomers used in emulsion polymerization include butadiene, styrene, acrylonitrile, acrylate ester and methacrylate ester monomers, vinyl acetate, acrylic acid and methacrylic acid, and vinyl chloride. All these monomers have a different stmcture and, chemical and physical properties which can be considerable influence on the course of emulsion polymerization. The first classification of emulsion polymerization process is done with respect to the nature of monomers studied up to that time. This classification is based on data for the different solubilities of monomers in water and for the different initial rates of polymerization caused by the monomer solubilities in water. According to this classification, monomers are divided into three groups. The first group includes monomers which have good solubility in water such as acrylonitrile (solubility in water 8%). The second group includes monomers having 1-3 % solubility in water (methyl methacrylate and other acrylates). The third group includes monomers practically insoluble in water (butadiene, isoprene, styrene, vinyl chloride, etc.) [12]. 

W. D. Waters, Modified Vinyl Ester Resin and Pipe Made Therefrom, U.S. Pat. 3,928,491 (1975). CTBN + epoxy resin + methacrylic acid gives polymer I. Styrene as polymer II. An ABCP composition of I and II. 

Polyvinylidene chloride (PVDC), a polymer formed from CH2=CCl2, is diiScult to formulate and is not used for any type of product by itself. It is usually manufactured as a copolymer with various monomers, including acrylonitrile, vinyl chloride, acrylic esters, or methacrylic esters. A unique property of PVDC copolymers is to prevent water and gases from diffusing through the film. In this way, PVDC copolymer films provide a vapor barrier, and are commonly used to wrap foods for storage. The commercial name Saran refers to both the PVDC homopolymer and its copolymers. Reference Spectrum 22 provides the IR and Raman spectra of a vinylidene... 

Binders, vehicles, or resins may be of several types. AUsyd resins are among the most common and are composed of polymers of alcohols and adds—thus the term alkyd -ale from alcohol, -yd standing for add). Acrylic resins are based on polymers of methacrylate and methyl methacrylate (esters. Figure 11.32) similarly, vinyl resins are derived from vinyl chloride. Urethanes (polyurethanes) and some silicon-based resins are also encountered. Watercol-or paints use gum arabic as a binder. This material is obtained from the sap of the acacia tree and, when dry, forms a dear, water-soluble polymer matrix. 

Emulsion polymerization is similar to suspension polymerization in the sense that the reaction also takes place in the presence of a water phase and the applied monomer forms a second liquid phase. However, in this case the added radical initiator is not soluble in the monomer droplets but in the water phase. To allow the monomer to come into contact with the initiator an emulsifier is added to the reaction mixture that creates micelles in the systems. By diffusion processes both monomer molecules and initiator molecules reach the micelle. Polymerization takes places and a polymer particle suspended in the water phase forms that is much smaller than the original monomer droplet (see Figure 5.3.12 for a graphical illustration of these steps). At the end of the overall emulsion polymerization process, all monomer droplets have been consumed by the polymerization reaction in the micelles. Typical emulsifiers for emulsion polymerization are natural or synthetic detergents, such as, for example, sodium palmitate or sodium alkyl sulfonates. Emulsion polymerization is very versatile and is applied for many polymers [e.g., PVC, styrene copolymers, poly(methacryl esters)] in batch, semi-continuous, and continuous processes. In some cases, the obtained polymer particles in water are directly applied as technical products for coatings, lacquer applications, or as adhesives. In other cases the formed product is further treated to obtain the dry polymer. Note that the aqueous phase in emulsion polymerization always contains some isolated emulsifier and also some monomer. Moreover, the formed polymer contains the emulsifier as impurity. 

The weight fi actions of the sorbed water were 4.7, 3.1, 2.3, 0.3, and 0.1wt% for PMANKA), PMANKB), PMANI(0, PPRNI(B), and PBZNI(B), respectively, at 95% relative humidity. For the PMANI series of polymers, a plot of weight fraction of water sorbed vs. mole firaction of NISS gave a linear line. The value extrapolated to 0% of NISS fraction was 1.1% which was in good agreement with the value (1.05%) measured for poly(methyl methacrylate). The introduction of NISS units into the polymers enhanced their water sorption ability. The more hydrophobic nature of the methacrylate ester groups decreased the water sorption abflity. 

Both acrylic acid and methacrylic acid polymerise to give water soluble hard resins. The viscous solutions so formed have been used as emulsifying agents, adhesives and as thickening agents for inks and dyes. Polymers of esters of these acids are of greater commercial importance. Esters can be prepared from cyanhydrins by reaction with an alcohol ... 

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