Methacrylic amine-neutralized

Short-chain monomers, in particular ethyl acrylate and methyl methacrylate in a volume ratio of 5 1, are introduced in liquid form without solvents in a dosed system. Low-intensity y-radiation polymerizes the monomers under ambient conditions. Additionally, the liquid monomer mixture has been modified to indude an amine-substituted alkyl methacrylate to neutralize acidity and establish a buffer against future acid catalyzed hydrolysis [34]. The presence of a small amount of a diacrylate leads to cross-linking and hence strengthening of the paper. 

Within the scope of the original definition, a very wide variety of ionomers can be obtained by the introduction of acidic groups at molar concentrations below 10% into the important addition polymer families, followed by partial neutralization with metal cations or amines. Extensive studies have been reported, and useful reviews of the polymers have appeared (3—8). Despite the broad scope of the field and the unusual property combinations obtainable, commercial exploitation has been confined mainly to the original family based on ethylene copolymers. The reasons for this situation have been discussed (9). Within certain industries, such as flexible packaging, the word ionomer is understood to mean a copolymer of ethylene with methacrylic or acryhc acid, partly neutralized with sodium or zinc. 

A waterborne system for container coatings was developed based on a graft copolymerization of an advanced epoxy resin and an acryHc (52). The acryhc-vinyl monomers are grafted onto preformed epoxy resins in the presence of a free-radical initiator grafting occurs mainly at the methylene group of the aHphatic backbone on the epoxy resin. The polymeric product is a mixture of methacrylic acid—styrene copolymer, soHd epoxy resin, and graft copolymer of the unsaturated monomers onto the epoxy resin backbone. It is dispersible in water upon neutralization with an amine before cure with an amino—formaldehyde resin. 

Emulsion breakers are made from acrylic acid or methacrylic acid copolymerized with hydrophilic monomers [148]. The acid groups of acrylic acid and methacrylic acid are oxalkylated by a mixture of polyglycols and polyglycol ethers to provide free hydroxy groups on the molecule. The copolymers are made by a conventional method, for example, by free radical copolymerization in solution, emulsion, or suspension. The oxalkylation is performed in the presence of an acid catalyst, the acid being neutralized by an amine when the reaction is complete. 

The preparation of fluorinated alcohols was carried out in multistep routes according to the reported procedures.1012 The synthesis of acrylic and methacrylic esters as shown in Table 11.1 was carried out in a fluorocarbon solvent such as Freon 113 by the reaction of the respective fluorinated alcohol with acryloyl chloride or methacryloyl chloride and an amine acid acceptor such as triethyla-mine with examples shown in Scheme 1. Other attempts to esterify the fluoroalcohols directly with acrylic acid or acrylic anhydride were not successful.11 Product purification by distillation was not feasible because of the temperature required, but purification by percolation of fluorocarbon solutions through neutral alumina resulted in products of good purity identified by TLC, FTIR, and H-, 13C-, and 19F- FTNMRs. 

In a related application, polyelectrolyte microgels based on crosslinked cationic poly(allyl amine) and anionic polyfmethacrylic acid-co-epoxypropyl methacrylate) were studied by potentiometry, conductometry and turbidimetry [349]. In their neutralized (salt) form, the microgels fully complexed with linear polyelectrolytes (poly(acrylic acid), poly(acrylic acid-co-acrylamide), and polystyrene sulfonate)) as if the gels were themselves linear. However, if an acid/base reaction occurs between the linear polymers and the gels, it appears that only the surfaces of the gels form complexes. Previous work has addressed the fundamental characteristics of these complexes [350, 351] and has shown preferential complexation of cationic polyelectrolytes with crosslinked car-boxymethyl cellulose versus linear CMC [350], The departure from the 1 1 stoichiometry with the non-neutralized microgels may be due to the collapsed nature of these networks which prevents penetration of water soluble polyelectrolyte. 

Acetals result from oxidative coupling of alcohols with electron-poor terminal olefins followed by a second, redox-neutral addition of alcohol [11-13]. Acrylonitrile (41) is converted to 3,3-dimethoxypropionitrile (42), an intermediate in the industrial synthesis of thiamin (vitamin Bl), by use of an alkyl nitrite oxidant [57]. A stereoselective acetalization was performed with methacrylates 43 to yield 44 with variable de [58]. Rare examples of intermolecular acetalization with nonactivated olefins are observed with chelating allyl and homoallyl amines and thioethers (45, give acetals 46) [46]. As opposed to intermolecular acetalizations, the intramolecular variety do not require activated olefins, but a suitable spatial relationship of hydroxy groups and the alkene[13]. Thus, Wacker oxidation of enediol 47 gave bicyclic acetal 48 as a precursor of a fluorinated analogue of the pheromone fron-talin[59]. 

For the past several years, our laboratory has studied the swelling properties of weakly basic, hydrophobic polymer gds. The gels are formed by bulk polymerization of hydro diobic n-alkyl methacrylates (n-AMA) with N,N-dimethylaminoethyl methacrylate (D( ), tte latter comonomer bearing a tertiary amine sidediain. To form a three-dimensional polymer network that will not dissolve upon swelling, small amounts of the crosslinker divinylbenzene (DVB) are added. These gds, when placed in aqueous solutions, absorb minimal amounts of water in neutral and alkaline media, but become swollen in addic media. Hence, they might be considered for applications in which drug release in the stomach is desirable. 

Having shown that carboxy terminated polyesters present typical surfactant characteristics after neutralization with amines, it was of interest to examine their application possibilities in emulsion polymerization. Such polymerizations for styrene and for butyl-methacrylate (BMA) have been carried out either by a batch technique or by a semi- continuous procedure. The reaction conditions were the following ... 

In the case of the epoxy-acrylic graft copolymer, the epoxy is not soluble in the monomer mixture, even as low as a 10% solution. However, the epoxy resin being the majority component acts as the continuous phase. The purpose of the graft epoxy-styrene-methacrylic acid copolymer is to lower the barrier at the interface so that a stable oil-in-oil emulsion is first obtained and upon neutralization with a tertiary amine, dimethyl ethanol amine, a stable oil-in-oil emulsion in water is then obtained. 

IV. The fourth type includes polymerization in the presence of ionic macromolecular emulsifier. In this case, monomers such as styrene, methyl methacrylate, methacrylic acid, acrylonitrle, etc. were polymerized with the neutralized epoxy-g-(methacrylic acid-styrene) copolymer as emulsifier. The initiator used was a redox system composed of sodium formaldehyde sulfoxylate-tert. butyl hydroperoxide. The base used for neutralization was dimethyl ethanol amine. 

Further work by Palermo and Kuroda extended the library of molecules to indude tertiary amine- and quaternary ammonium-fimctionalized methacrylates. For this series, cationic monomers were polymerized with methyl and butyl acrylate monomers. As with the styrene-based polymers of Gelman et al, the quaternary ammonium series was much less antimiaobial and somewhat less hemolytic than the primary and tertiary amine series. Again, titration of the polymers showed that there is partial deprotonation of the amine functionalities at neutral pH. The deprotonated moieties are more hydrophobic than the ammonium salts, and thus inaease the membrane activity of the polymers. No explanation was given, however, for the inaeased activity of the primary amine polymers over the tertiary amine polymers. 

Zinc neutralized, ethylene-methacrylic acid copolymer ionomer Zinc carboxylate Low reactivity with amine but good polar interaction of Zn with amide and amine groups (interfacial complexation) Tg not low cmough, limits low temp, toughness Good solvent resistanee... 

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