Polymeric emulsifiers

The second generation includes latices made with functional monomers like methacrylic acid, 2-hydroxyethyl acrylate [818-61 -17, acrylamide/75 -(9ti-/7, 2-dimethylaminoethylmethacrylate [2867-47-2] and sodiumT -vinyl-benzenesulfonate [98-70-4] that create in polymeric emulsifier. The initiator decomposition products, like the sulfate groups arising from persulfate decomposition, can also act as chemically bound surfactants. These surfactants are difficult to remove from the latex particle. 

Chemically related database searches can be used to estabhsh concepts and patentable ideas. For instance, searches have identified researchers using particular monomers in a potentially patentable latex formulation found precedents for a polymeric emulsifier summarized pubHcations of people being considered as consultants, expert witnesses, employees or speakers to an industrial group and provided market description information for a new pigment manufacturing firm to identify target markets. 

Emulsion polymerization is the most important process for production of elastic polymers based on butadiene. Copolymers of butadiene with styrene and acrylonitrile have attained particular significance. Polymerized 2-chlorobutadiene is known as chloroprene rubber. Emulsion polymerization provides the advantage of running a low viscosity during the entire time of polymerization. Hence the temperature can easily be controlled. The polymerizate is formed as a latex similar to natural rubber latex. In this way the production of mixed lattices is relieved. The temperature of polymerization is usually 50°C. Low-temperature polymerization is carried out by the help of redox systems at a temperature of 5°C. This kind of polymerization leads to a higher amount of desired trans-1,4 structures instead of cis-1,4 structures. Chloroprene rubber from poly-2-chlorbutadiene is equally formed by emulsion polymerization. Chloroprene polymerizes considerably more rapidly than butadiene and isoprene. Especially in low-temperature polymerization emulsifiers must show good solubility and... 

Harris, J. R., Investigation of Bunte Salts as Potential Polymeric Emulsifying and Crosslinking Agents. Ph.D. Dissertation, The University of Southern Mississippi, 1986. 

Styrene as matrix and polybutadiene as dispersed phase. During this phase inversion the above-mentioned graft copolymers act as polymeric emulsifiers and determine, inter alia, the particle size and particle size distribution of the dispersed polybutadiene phase. This morphology is fixed through another chemical reaction, that is the crosslinking of the polybutadiene phase. Therefore, the reaction mixture at the end of the prepolymerization period (at 30% conversion) does scarcely alter its morphology when it is polymerized to complete conversion, which is done without stirring mostly in bulk in a separate vessel. 

Polymeric emulsifier mixed with nonionic nonpolymeric coemulsifier Polyalkoxylated amines... 

Polyalkoxylates Polyalkoxylate amine Planteren 600 CPUS Polymeric emulsifiers Twin-tailed QAS... 

The monomer can be polymerized either directly, that is undiluted (block or substance polymerization), or in the presence of a non-polymerizable solvent (solvent polymerization). In the first case there is a problem with dissipating the localized heat of reaction (traces of decomposition products result from overheating) and in the second case the solvent must be completely removed. Other possibilities are to suspend the monomers in dispersions, e.g. in water (suspension or pearl polymerization), or eventually using an emulsifier (emulsion polymerization). Emulsifiers and dispersants are considered to be processing aids for the production of polymers. 

There are an enormous variety of commercial emulsifiers that are employed in emulsion polymerization. Emulsifiers are generally categorized into four major classes anionic, cationic, nonionic and zwitterionic (amphoteric). The anionic and nonionic emulsifiers are the most widely used. In addition, mixtures of emulsifiers are also often used. Since the effects of the molecular structme and chemical and physical properties of an emulsifier on particle formation are still far from being well understood, numerous experimental investigations on particle formation have been carried out to date with various nonionic emulsifiers [99-102], mixed emulsifiers (ionic and nonionic emulsifiers) [18,103-106] and reactive surfactants [33, 107-110]. Recently, polymeric surfactants have become widely used and studied in emulsion polymerizations [111-116]. A general review of polymeric surfactants was published in 1992 by Piirma [117]. Recently, emulsion polymerization stabilized by nonionic and mixed (ionic and nonionic) emulsifiers was reviewed by Capek [118]. 

Some natural polymeric emulsifiers such as the gums, in addition to forming steric and electrostatic... 

Sulphonated natural oils, sulphonated oleic acid esters and a-ester sulphonates were investigated as polymerization emulsifiers and have been successfully used as special emulsifiers for establishing certain product properties [49]. Fatty alcohol sulphates have been used as emulsifiers since the very begirming of emulsimi polymerization, and are distinguished by particularly good polymerizatiOTi behaviour and by formation of... 

Values corresponding to surfactants or charged polymeric emulsifiers (only those actually synthesized) that lead preferentially to the formation of OAV and W/O emulsions appear respectively in white and black rectangles. Grey rectangles display HLB values of the most balanced emulsifiers. 

Tamburic S, Vuleta G, Simovic S, Milic J. Rheological evaluation of OAV cream bases containing polymeric emulsifiers. SOFW J 1998 124 204-209. 

Simovic S, Milic-Askrabic J, Vuleta G, Ibric S, Stupar M. The influence of processing variables on performance of OAV emulsion gels based on polymeric emulsifier (Pemulen TR-2NF). International J Cosmetic Sci 1999 21 119-125. 

Mathur AM, Drescher B, Scranton AB, Klier J. Polymeric emulsifiers based on reversible formation of hydrophobic units. Nature 1998 392 367-370. 

Kuo PL, Chen CJ. Functional polymers for colloidal applications. V. Novel behavior of polymeric emulsifiers in emulsion polymerization. J Polym Sci, Part A Polym Chem 1993 31 99-111. 

Lee DY, Kim JH. Emulsion polymerization using alkali-soluble random copolymer as a polymeric emulsifier. Am Chem Soc Polym Prepr 1997 38(2) 418-419. 

Kato S, Noguchi J, Nomura M. Kinetics of emulsion polymerization of methyl methacrylate using poly(methyl methacrylate-co-methacrylic acid) as polymeric emulsifier. Polym Mat Sci Eng 1999 80 552—553. 

In a typical emulsion polymerization, emulsifier, initiator, and buffer are dissolved in deionized water and are fed continuously to... 

Astrowet. [Alco] Sulfosuccinates polymerization emulsifier, wetting agmit... 

Diprosin. [TohoChem. Industry] Dispro-portionated rosins polymerization emulsifier for synttetic rubbers and plastics. 

Research sponsored by the government and private corporations has contributed much to the understanding of fundamentals that govern the complex process of emulsion polymerization. Emulsifiers play the triple role of emulsifsdng the monomers, furnishing micelles which are the sites of polymer initiation, and stabilizing the latex during the polymerization and afterward. To obtain satisfactory rates of polymerization at low tem-... 

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