MPEO45-CL6.5-LA (the subscripts refer to the average number of repeating monomer units) was found to be the most suitable surfactant, as it performs adequately under suboptimal reaction conditions. To optimize polymerization conditions and to avoid coagulation and solidification during the reaction, the temperature, the amount of initiator, the chemical characteristics of the surfactant, and the surfactant to monomer ratio were varied. The system was stabilized using, linoleic acid (LA)-functionalized and nonfunctionalized surfactants based on methoxy-PEG (MPEG) and ε-caprolactone (CL). Characterizations and applications for biobased latex.A redox initiating system, consisting of t-butyl hydroperoxide (tBHPO), isoascorbic acid (iAA), and ethylenediaminetetraacetic acid ferric-sodium salt (FeEDTA) was employed in emulsion polymerizations of methyl methacrylate (MMA) at high solids contents of 30 wt % in water.Biobased surfactants and pickering emulsions.Reactive latex and cross-linkable coatings.Reactivity and molar mass issues in emulsion polymerization.Innovative and promising bio-based monomers for industrial polymers.The objective is to address issues and gaps concerning: We propose to gather the highest-level contributions from the academic and industrial communities on these remaining challenges. Developing greener coatings is certainly important, but companies are also concerned with the reduction of waste and the carbon footprint.
Finally, functional coatings which avoids the superposition of several coatings for same properties is also an economic and environmental advantage. Hence the substitution or replacement of these surfactants is still important. Additionally, some toxic surfactants or additives could leach out of the final coatings. Hence, crucial challenges such as the substitution of styrene and other harmful petro-based acrylates remain. Moreover, most emulsion polymers are prepared from relatively harmful monomers such as acrylates, styrene or isocyanates. Hence, numerous bio-based emulsion polymers have been developed from vegetable oils or sugar derivatives to yield bio-based latex. The desire and need for more sustainable and more energy efficient materials have encouraged the use of more bio-based and safer chemicals. Aqueous polymerization in dispersed media includes several related processes such as emulsion polymerization, miniemulsion polymerization, microemulsion polymerization, dispersion polymerization and suspension polymerization. Moreover, it reduces the reaction medium viscosity and improves heat transfer enabling easier reaction temperature control. The use of water as a continuous phase has already several advantages, as it is an innocuous and nonflammable solvent. Nowadays, companies are looking at “green” coatings and sustainability from a holistic standpoint. However, meeting environmental regulations is not enough. In the past, paint and coatings industry focused research and development efforts to develop low VOC technologies for paints, binders and sealants.
Sustainability is one of the most discussed issues in the industry. Organizers: Sylvain Caillol, Institut Charles Gerhardt Montpellier Vincent Ladmiral Dean Webster
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