Methacrylic acid copolymers latex

Polymers for Advanced Technologies 9, No. 12, Dec.1998, p.844-50 STUDY OF POLY(STYRENE/BUTYL ACRYLATE/METHACRYLIC ACID) COPOLYMER LATEXES WITH TRIMODAL PARTICLE SIZE DISTRIBUTION Fuxiang Chu Guillot J Guyot A CNRS-LCPP... 

Polymers of acrylic acid and methacrylic acid have been tested for their gel-formation ability [1396]. They are used with gel-forming additives similar to those described for polyacrylamides. Also, mixtures of latex with methacrylate-methacrylic acid copolymer as an additive have been described as plugging agents [1041]. 

V. L. Kuznetsov, G. A. Lyubitskaya, E. 1. Kolesnik, E. N. Kazakova, B. M. Kurochkin, and V. N. Lobanova. Plugging solution for isolating absorption zones in oil and gas wells—contains prescribed synthetic latex, water soluble salt of methacrylate-methacrylic acid copolymer as additive, and water. Patent RU 2024734-C, 1994. 

In the agglomeration step, the latexes are partially agglomerated using a core/shell agglomerating agent latex, which consists of an elastomeric 1,3-butadiene/slyrene copolymer core and an ethyl acrylate/methacrylic acid copolymer shell. This partial agglomeration operation should not be confused with a coagulation operation where the emulsion is fully destabilized (13). 

A 62 35 3 ethyl acrylate-methyl methacrylate-acrylic acid copolymer latex was prepared by continuous addition of the monomer mixture over a 4-hour period at 80° (22). The emulsifier was a sodium lauryl ether sulfate-nonylphenol polyoxyethylene adduct (20 moles ethylene oxide) mixture, the initiator a potassium persulfate-sodium hydroxulfite mixture, and the buffer a sodium bicarbonate-potassium hydroxide mixture. The final latex of pH 6.5 contained 40% solids, and the Tg of the copolymer was 13°. 

Butyl acrylate/methyl methacrylate/methacrylic acid copolymers with silylated latexes were prepared essentially according to a general procedure suitable to real-world systems. 

Many investigators have studied polymer surfaces for years [74,75] and have been successful in determining combinations of two or more valence states [76,77] by the mathematical process of deconvoluting the peak assignments [78]. It was only recently that latexes were examined by ESCA. Davies et al. [79] prepared a series of homopolymers of poly(methyl methacrylate) (PMMA) and poly(butyl methacrylate) (PBMA), and also poly[(methyl methacrylate)-co-(butyl methacrylate)] (PMMA-PBMA), by surfactant-free emulsion polymerization. It was found that the surface of the latex film was rich in PMMA, which may possibly be explained by the reactivity ratios for the MMA/BMA system (ri = 0.52 and rj = 2.11) [80], Recently, Arora et al. carried out angle-dependent ESCA studies on a series of films prepared from core-shell ionomeric latexes (with a polystyrene core and a styrene/n-butyl acrylate/ methacrylic acid copolymer shell) to determine the distribution of carboxyl groups in the films [81,82]. 

Latex with hydroxyl functionalised cores of a methyl methacrylate/butyl acrylate/2-hydroxyethyl methacrylate copolymer, and carboxyl functionalised shells of a methyl methacrylate/butyl acrylate/methacrylic acid copolymer was prepared by free radical polymerisation. The latex was crosslinked using a cycloaliphatic diepoxide added by three alternative modes with the monomers during synthesis dissolved in the solvent and added after latex preparation and emulsified separately, then added. The latex film properties, including viscoelasticity, hardness, tensile properties, and water adsorption were evaluated as functions of crosslinker addition mode. Latex morphology was studied by transmission electron and atomic force microscopy. Optimum results were achieved by introducing half the epoxide by two-step emulsion polymerisation, the balance being added to the latex either in solution or as an emulsion. 8 refs. 

Acrylics. Acetone is converted via the intermediate acetone cyanohydrin to the monomer methyl methacrylate (MMA) [80-62-6]. The MMA is polymerized to poly(methyl methacrylate) (PMMA) to make the familiar clear acryUc sheet. PMMA is also used in mol ding and extmsion powders. Hydrolysis of acetone cyanohydrin gives methacrylic acid (MAA), a monomer which goes direcdy into acryUc latexes, carboxylated styrene—butadiene polymers, or ethylene—MAA ionomers. As part of the methacrylic stmcture, acetone is found in the following major end use products acryUc sheet mol ding resins, impact modifiers and processing aids, acryUc film, ABS and polyester resin modifiers, surface coatings, acryUc lacquers, emulsion polymers, petroleum chemicals, and various copolymers (see METHACRYLIC ACID AND DERIVATIVES METHACRYLIC POLYMERS). 

Neoprene latex 115 contains a copolymer of chloroprene and methacrylic acid, stabilized with polyvinyl alcohol [15], With respect to other polychloroprene latices, this latex has two major advantages (1) excellent colloidal stability, which gives high resistance to shear and a broad tolerance to several materials ... 

The resins used are polymers and copolymers of the esters of acrylic and methacrylic acids. They range in physical properties from soft elastomers to hard plastics, and are used in cementitious compounds in much the same manner as SBR latex. Acrylics are reported to have better UV stability than SBR latex and therefore remain flexible under exterior exposure conditions longer than SBR latex [88]. 

Poly(acrylic acid) is water soluble. Because of its water solubility and its ability to increase the viscosity of water, it is used as a thickener. It is also a good flocculent for sewage treatment and is added as a pigment dispersant in latex paints, and is used in binders and adhesives. Polymers and copolymers containing acrylic or/and methacrylic acid are manufactured at a rate of about 2,000,000 metric tons yearly. 

The thermal transitions obtained for the p-St and p-BA homopolymers, and for the blend of these two homopolymers, are the anticipated transitions. The St/BA (65/35) copolymer exhibits a single transition at 33°C which is in the temperature region expected for that copolymer composition. The 65//35 (St//BA) two-stage latex exhibits the p-St and p-BA transitions in addition to a transition in the corresponding copolymer range. This intermediate transition was also observed when a mixture of 98 parts n-butyl acrylate and 2 parts methacrylic acid was used as the second stage composition or if AIBN was used as the second stage initiator. A tentative interpretation is that this transition is... 

Inaba et al. prepared a series of model styrene/butyl acrylate copolymer latexes with glass transition temperatures at room temperature. The functional monomer 2-(3-isopropenylphenyl)-2-methylethylisocyanate (TMI) was used as monomer/crosslinking agent for further film formation. A small amount of methacrylic acid was introduced in some formulations in order to enhance the crosslinking reaction. A redox initiation system was used to reduce premature crosslinking during the polymerization [82]. 

Fig. 29. Proton NMR spectrum of the copolymer latex (in CDC13) for a mole feed ratio of methacrylic acid to styrene of 0.12, internal phase ratio 0.93, AIBN 0.3 g, SDS 0.4 g and water 3 ml, polymerized first for 12 h at 40 °C. After this polymerization, additional water (twice as much as the weight of the emulsion) was added into the tubes, then polymerization continued for 2 days...

Since the methacrylic acid molecules are soluble in both styrene and water, it is important to determine the efficiency of its incorporation in the copolymer latexes. Figure 29 is an H-NMR spectrum of the copolymer latexes. The NMR peak areas of the phenyl (at 6.2-7.4 ppm) and methyl (at about 0.5 ppm) protons allow one to calculate the composition of copolymer latexes. Table 5 lists the compositions and sizes of the copolymer latexes obtained. The efficiency is quite high and increases with increasing amount of methacrylic acid. 

After the paper making process is complete, latexes that are useful as binders for the application of clays or CaCC>3 to paper for printing paper may be prepared using the dimer of AMS. In a typical formulation, styrene, butadiene, Me methacrylate, and acrylonitrile were emulsion polymerized in the presence of AMS dimer to obtain a copolymer latex.473 Surprisingly, the AMS dimer was used in combination with tert-dodecylmercaptan, so there may have been some residual odor. Unsaturated carboxylic acids, such as acrylic acid, or sulfonic acids, such as 2-ethylsulfonyl acrylate, or unsaturated amides, such as acrylamide, are also useful, providing the polarity necessary in these applications.474... 

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