Dispersion acrylic main

Waterborne dispersed polymers include both synthetic polymer dispersions and natural rubber. Synthetic polymer dispersions are produced by emulsion polymerization. A substantial part of the synthetic polymer dispersions is commercialized as dry products these include SBR for tires, nitrile rubbers, about 10% of the total PVC production, 75% of the total ABS and redispersable powders for construction materials. Carboxylated styrene-butadiene copolymers, acrylic and styrene-acrylic latexes and vinyl acetate homopolymer and copolymers are the main polymer classes commercialized as dispersions. The main markets for these dispersions are paints and coatings, paper coating, adhesives and carpet backing. 

There are probably several factors which contribute to determining the endo exo ratio in any specific case. These include steric effects, dipole-dipole interactions, and London dispersion forces. MO interpretations emphasize secondary orbital interactions between the It orbitals on the dienophile substituent(s) and the developing 7t bond between C-2 and C-3 of the diene. There are quite a few exceptions to the Alder rule, and in most cases the preference for the endo isomer is relatively modest. For example, whereas cyclopentadiene reacts with methyl acrylate in decalin solution to give mainly the endo adduct (75%), the ratio is solvent-sensitive and ranges up to 90% endo in methanol. When a methyl substituent is added to the dienophile (methyl methacrylate), the exo product predominates. ... 

Acrylic acid, the main precursor to acrylic adhesives had been synthesized in the mid 1800s and the first acrylic acid esters were made and characterized at the turn of the century [62]. The first commercial launch of acrylic polymers in the form of poly(methylmethacrylate) took place in 1927 when the German company Rohm and Haas AG introduced this new plastic to the market. Soon after, other companies such as BASF introduced acrylic dispersions. 

There are numerous applications where the development of high viscosity is necessary in a finished product. For example, thickeners, mainly based on poly(acrylic acid), are used to give body to so-called emulsion paints. Emulsion paints are not formulated from true emulsions (Le. stable dispersions of organic liquids in water), but are prepared from latexes, that is, dispersions of polymer in water. Since latexes do not contain soluble polymers, they have a viscosity almost the same as pure water. As such, they would not sustain a pigment dispersion, but would allow it to settle they would also fail to flow out adequately when painted on to a surface. Inclusion of a thickener in the formulation gives a paint in which the pigment does not settle out and which can readily be applied by brush to a surface. 

Copolymers of mainly acrylic acid and 2% to 20% by weight of itaconic acid are described as fluid loss additives for aqueous drilling fluids [138]. The polymers have an average molecular weight between 100,000 and 500,000 Dalton and are water dispersible. The polymers are advantageous when used with muds containing soluble calcium and muds containing chloride ions, such as seawater muds. 

The three most important types of synthetic fibres used commonly as textiles are polyester, polyamides (nylon) and acrylic fibres. Polyester and the semi-synthetic fibre cellulose acetate are dyed almost exclusively with the use of disperse dyes. Polyamide fibres may be coloured using either acid dyes, the principles of which have been discussed in the section on protein fibres, or with disperse dyes. Acrylic fibres are dyed mainly using basic (cationic) dyes. 

At one time disperse-type FBAs, such as pyrazoline, coumarin or naphthalimide derivatives, were commonly used to brighten acrylic fibres. Today all the important brighteners for these fibres are cationic in character and can be divided into two main categories ... 

The split into the various textile dyestuff application areas has, over recent years, seen a shift towards the two main outlets of disperse dyes for polyester and reactive dyes for cellulosics (mainly cotton), at the expense of directs and vat dyes for cotton, cationic dyes for acrylics and acid dyes for polyamide. The latter fibre has shown a comeback in recent years with the popularity of microfibres in sports and leisure wear. The position in 1998, with disperse dyes dominating in value terms, was as shown in Table 2.6. 

In the following review there are six technical sections, the first three covering dyes. The division has been made on the basis of the nature of the electronic character of the dye molecule. Anionic dyes are applied to hydrophilic fibres whilst cationic dyes are applied mainly to acrylic fibres. The neutral disperse dyes are used mainly on the hydrophobic polyester fabrics. Then follow sections covering pigments, a short summary of fluorescent brightening agents and, finally, an introduction to the subject of colour and chemical constitution. 

A waterborne system for container coatings was developed based on a graft copolymerization of an advanced epoxy resin and an acrylic (52). The acrylic—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 aliphatic backbone on the epoxy resin. The polymeric product is a mixture of methacrylic acid—styrene copolymer, solid 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. 

Polymers based on acrylic acid are highly hydrophilic and are utilized in different applications that include superadsorbent materials, flocculants and dispersants. Polyacrylates and their copolymers range from soft and flexible materials to hard plastics, applied in the production of coatings, paints, binders and adhesives. Their applications include the manufacture of cars e.g., coatings, upholsteries and adhesives) and the textile e.g., binders for fiberfill and nonwoven fabrics), paper and leather industries. Methyl acrylate is mainly utilized for copolymerization with acrylonitrile to improve the dyeability of fibres. 

Most vinyl acetate is converted into polyvinyl acetate (PVA) which is used in the manufacture of dispersions for paints and binders and as a raw material for paints. It is also copolymerized with vinyl chloride and ethylene and to a lesser extent with acrylic esters. A substantial proportion of vinyl acetate is converted into polyvinyl alcohol by saponification or transesterification of polyvinyl acetate. The main applications for polyvinyl alcohol are either as raw material for adhesives or for fibres. It is also employed in textile finishing and paper glueing, and as a dispersion agent (protective colloid). The world production capacity of PVA was 4.35 Mt/a in 2005, of which 2.1 Mt were converted into polyvinyl alcohol. 

Disperse (or plastosoluble) dyes are partially soluble in water and are used to color synthetic fibers like polyester, acrylic and acetate, and sometimes nylon, particularly in stockings. They are not employed for natural fibers. These molecules are the main sensitizers among the dyes. Women seem to be more prone than men to become sensitized but these data are not consistent. 

Alkyl phenol ethoxylates can also react with P4O10 yielding alkyl phenol etherphosphates as a mixture of mono-/diesters or with maleic anhydride to yield maleic acid monoesters, which then react with NaHS03 to yield sulphosuccinate monoesters. Alkylphenolpolyglycolether sulphates, phosphates or sulphosuccinates are mainly used as primary anionic emulsifiers for the manufacturing of acrylic, styrene/acrylic or vinyl acetate co-polymer dispersions. Another type of non-ionic emulsifier is block copolymers of ethylene oxide with propylene oxide. 

On account of its low thermal stability, polyfvinylidene chloride) is seldom used in paints. Vinylidene chloride copolymers with vinyl chloride, acrylonitrile, or acrylates are mainly employed. These heat-sealable copolymers are efficient gas barriers and have an outstanding resistance to chemicals. They are marketed as solid resins and dispersions. Vinylidene chloride copolymers are mainly used for coating foodpackaging foils. They are also important in paint coatings where good chemical resistance is required. 

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