Polyacrylate comonomers

For the characterization of Langmuir films, Fulda and coworkers [75-77] used anionic and cationic core-shell particles prepared by emulsifier-free emulsion polymerization. These particles have several advantages over those used in early publications First, the particles do not contain any stabihzer or emulsifier, which is eventually desorbed upon spreading and disturbs the formation of a particle monolayer at the air-water interface. Second, the preparation is a one-step process leading directly to monodisperse particles 0.2-0.5 jim in diameter. Third, the nature of the shell can be easily varied by using different hydrophilic comonomers. In Table 1, the particles and their characteristic properties are hsted. Most of the studies were carried out using anionic particles with polystyrene as core material and polyacrylic acid in the shell. 

The pyrolysate of polyacrylic-/nfer-nef-polysiloxane copolymer contains as main fragment molecules pyrolysis products similar to those of poly(butyl acrylate) and of poly(dimethylsiloxane (see Figure 6.7.8. and Section 16.1). The identification of fragments that would indicate sequences of other comonomers or any molecular connections between the two types of comonomer units was not possible. Other copolymers with acrylic acid as comonomer were studied using analytical pyrolysis. Among these are copolymers with special properties such as the copolymer with the formula shown below ... 

Quite frequently, copolymerization is used to optimize the properties of polyacrylates. For example, copolymers of ethyl acrylate with methyl acrylate provide the required hardness and strength, while small amounts of comonomers with hydroxyl, carboxyl, amine, and amide functionalities are used to produce high-quality latex paints for wood, wallboard, and masonry in homes. These functionalities provide the adhesion and thermosetting capabilities required in these applications. Monomers with the desired functional groups most often used in copolymerization with acrylates are shown in Table 15.8. 

Polyacrylates as binders consist of copolymers of acrylate and methacrylate esters. Other unsaturated monomers (e.g., styrene and vinyltoluene) may also be incorporated, but usually to a lesser extent. Copolymers formed exclusively from acrylates and/or methacrylates are termed straight acrylics. The comonomers differ as regards the alcohol residues of the ester group, which also allow incorporation of additional functional groups. Choice of suitable monomers allows wide variation of the physical and chemical properties of the resulting polymer. Hydrophilicity, hydrophobic-ity, acid base properties as well as can be adjusted resins containing hydroxyl, amine, epoxy, or isocyanate groups can also be produced. 

On-line coupling of pyrolysis, gas chromatography, and mass spectrometry is a quick and elegant method for the qualitative detection of monomer units in many resins (e.g., polyesters, polyurethanes, phenolic resins, and polyacrylates). Identification of comonomers of polyacrylates, including hydroxy-functional and carboxy-functional monomers, is facilitated if the sample is silylated before pyrolysis [10.30]. 

Uses Carboxylated comonomer for polyacrylic and polymethacrylic acids, other acrylic acids, acrylic polymers, styrene-butadiene, vinyl acetate, nitrile latex comonomer for radiation-cured polyester/polyurethane resin paints antimigrant for pigment pad dyeing pigment print emulsifier... 

Some commercial low molecular weight polyacrylamides (LMPAM) are manufactured in solution and sold at 10-50% solids. For example, LMPAM containing DADMAC comonomer is made at 40% solids and can be reacted with glyoxal to produce a strengthening resin for paper. Furthermore, LMPAM hydrolyzed with sodium hydroxide to polyacrylate is manufactured at 30% solids and is used as an antisealant. High molecular weight poly(acrylamide) is also prepared in solution at 2-6 wt% solids and is often further modified using, for example, the Mannich reaction. 

The new polyacrylic fibers (OHIS, Skopje) contain incorporated AMPS, which gives new and improved dyeing properties to the fiber. It can be dyed in more brilliant hues compared to Malon fiber with itaconic acid as an acidic comonomer (171). 

The number of resin emulsions and rubber latexes suitable for use as raw materials for adhesives is very large. Emulsions of homopolymers and copolymers of vinyl acetate are the most important. The comonomers for vinyl acetate include maleic esters, acrylates, ethylene and vinyl chloride, unsaturated carboxylic acids, and vinyl esters of relatively long-chain fatty acids, such as vinyl laurate. Apart from these products, polyacrylate homopolymers and copolymers and also styrene copolymers are particularly important in adhesives [42]. 

Acrylics. Polyacrylates are copolymerized from different monomeric acrylates, optionally with some vinyl compounds. By selecting suitable comonomers, the Tg and the surface energy can be adjusted over a wide range. The most important monomers are listed in Table 2. 

---