Microgelation of unsaturated polyester resins in the presence of poly(vinyl acetate) by static and dynamic light scattering

Effect of Poly(ethylene oxide) Homopolymer and Two Different Poly(ethylene oxide-b-poly(propylene oxide)-b-poly(ethylene oxide) Triblock Copolymers on Morphological, Optical, and Mechanical Properties of Nanostructured Unsaturated Polyester

“…These values indicate weak contribution of UPol and strong contribution of St to the miscibility of PPO with UP resin. The last is in good agreement with the results reported in the literature. − Consequently, taking into account the phase diagram of Figure and that the PPO block content in the 15%EPE75 mixture was ca. 3 wt %, it could be confirmed that no phase separation of PPO central block would take place in the UP/EPE75 mixtures from 25 to 80 °C.…”

Relationship between the Morphology of Nanostructured Unsaturated Polyesters Modified with PEO-b-PPO-b-PEO Triblock Copolymer and Their Optical and Mechanical Properties

“…Those values indicate high compatibility between PPO and St and a very low one between UPol and PPO, which is in good agreement with the results reported in the literature. 24,33,41 Thus, T g-UP could be associated with a phase composed of UPol, St, and PEO (UPol-rich phase), whereas T g-EPE could be associated with a separated phase composed of PPO and St (PPO-rich phase). Consequently, the changes in both T g-UP and T g-EPE can be related to a distribution of St between the UPol-rich phase and the PPO-rich phase.…”

Unsaturated Polyesters and Vinyl Esters

“…Figure 6.22 [133] illustrates the changes in morphology during the cross-linking process of UPR. Figure 6.22a represents the initial state of the resin where the unsaturated polyester chains are distributed homogeneously within the styrene co-monomer.…”

“…In principle, this process is the same when UPR cross-linking takes place in the presence of LPA when the coiled UP chains are swelled in a mixture of LPA and styrene [133]. However, while the reaction kinetics of the cross-linking was affected only to a minor extent by LPAs like cellulose acetate butyrate [142] or PVAc [143], lower overall degrees of curing [144,145] were observed and the micro-gel formation already took place at a lower degree of conversion and led to a higher gel conversion [141,139].…”

“…22 Schematic representation of the morphological changes in UPR during the curing reaction of UPR containing no low-profile additive: (a) Beginning of the curing reaction, (b) micro-gel formation resulting from intramolecular cross-linking, (c) intermolecular cross-linking between the microgel particles, and (d) macro-gelation[133].…”