Polymeric latexes produced in emulsion have a wide range of industry applications, mainly for manufactured of water-borne coatings that require the formation of a continuous film with high mechanical strength that in turn are strongly depend on the operational conditions, chemical composition and molecular-weight distribution responsible for important end use properties of the film such as adhesion, elasticity, mechanical strength and toughness. However, due to both, heterogeneous and compartmentalized nature of emulsion polymerizations process added the lack of adequate online instrumentation make it difficult the development of robust model and online measure of key properties such as composition and molecular-weight that usually are measured offline, with long sampling intervals and delays. Traditionally, the control of polymeric latexes properties has been carry out by copolymer composition control, obtained from different sensors such as gas chromatography, calorimetry, and Raman, NIR and MIR spectroscopies among others. On the other hand, the online and simultaneous estimation of molecular-weight distribution and copolymer composition still an unsolved issue. In general the molecular-weight distribution can be obtained by offline measure of size exclusion chromatography (SEC) that consuming long sampling intervals making impracticable its implementation to monitoring of polymerization reactions. Amongst the control methods the calorimetry has been showed a simple and right technique for online monitoring and control of copolymer accumulated composition and molecular-weight distribution during copolymerizations reactions due make possible the measurement noninvasive, rapid and robust besides be a technique that can be easily implemented in industrial environment. However, the most works related to this subject, focuses only semicontinuous process being reduced the number of works related to the control of copolymer composition and molecular-weight distributions of copolymers obtained by reactions carried out in tubular reactors or emulsion copolymerizations reactions carried out to high pressures such as reactions that involve styrene/butadiene couple monomers. Therefore, the goal of this work is to implement strategies of online and simultaneous estimation of accumulated copolymer composition and molecular-weight distribution as well as to implement strategies to control these parameters during seeded and unseeded semicontinuous and continuous emulsion copolymerization reactions involving the following pairs of monomers: methyl methacrylate/butyl acrylate, styrene/butadiene, and vinyl acetate/butyl acrylate using calorimetric techniques.
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