Microgel introduction

Different ways of toughening thermosets may be employed such as the use of rubber block copolymers (Mulhaupt and Buchholz, 1996) or introduction of microgels (crosslinked microparticles) (Funke et al., 1998). 

Poly(N-isopropylacrylamide) (PNIPAM) is the most studied thermosensitive polymer in aqueous media. It is soluble in water at low temperatures but becomes insoluble when the temperature is increased above a certain temperature ( 32 °C) (lower critical solution temperature), which is related to the coil-to-globule transition [64, 65]. In the case of a polymer network, a volume change occurs reversibly within a narrow temperature range. The properties of such microgels can be varied to a great extent by the introduction... 

Keywords microgel particles, core-shell particles, controlled release, triggered release 1. Introduction... 

Microgel particles have been demonstrated to be good substrates for the immobilization of enzymes, which retain their catalytic efficiency [124], However, the design of a carrier system in which the catalytic efficiency can be regulated by some extrinsic stimulation such as temperature, pH, ion intensity, or magnetism remains a challenge. Very recently, Liu et al. [125] have reported the introduction of glutathione... 

As described in the Introduction, Dusek [35] emphasized the importance of cyclization and quite recently, Dotson [36] has argued it again. Here it should be noted that they have treated indiscriminately both intramolecular cyclization (2) and intramolecular crosslinking (4) as cyclization and strongly emphasized the marked occurrence of such cyclization at a quite early stage of polymerization where no intermolecular crosslinking occurs. Eventually, the enhanced reactivity of pendant double bonds because of their spacial proximity to the terminal radical site would lead to the formation of microgel at a low conversion. 

Hence, the authors of paper [30] have demonstrated that the introduction in the consideration of stmctme of forming in curing reaction process microgels. 

Microgels can be prepared which are sensitive to pH, electrolyte concentration, light intensity or the introduction of a co-solvent (non-solvent) to their environment. 

Pelton, R., Hoare, T., 2011. Microgels and their synthesis an introduction. In Fernandez-Nieves, A., Wyss, H.M., Mattsson, J., Weitz, D.A. (Eds.), Microgel Suspensions Fundamentals and Applications. Wiley-VCH, Singapore, pp. 3-32. 

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