Waterborne hyperbranched alkyd-acrylic resin obtained by miniemulsion polymerization

Abstract

SbstractFour waterborne hyperbranched alkyd-acrylic resins (HBRAA) were synthesized by miniemulsion polymerization from a hyperbranched alkyd resin (HBR), methyl methacrylate (MMA), butyl acrylate (BA) and acrylic acid (AA), by using benzoyl peroxide (BPO) and ammonium persulfate (AP) as initiators. The reaction between HBR and acrylic monomers was evidenced by differential scanning calorimetric (DSC), nuclear magnetic resonance (NMR) and gel permeation chromatography (GPC). The conversion percentage, glass transition temperature (T g ), content of acrylic polymer (determined by soxhlet extraction) and molecular weight increased with the content of acrylic monomers used in the synthesis. The main structure formed during the synthesis was the HBRAA. The analysis by dynamic light scattering (DLS) showed that the particle size distribution of HBRAA2, HBRAA3 and HBRAA4 resins were mainly monomodal. The film properties (gloss, flexibility, adhesion and drying time) of the HBRAA were good.

Waterborne star‐shaped styrene‐alkyd resins

“…It can be inferred that despite the formation of PS, high GD values were obtained. On the other hand, the GD values found in this study were lower than those reported for alkyd‐acrylic resins prepared by miniemulsion polymerization whose values were higher than 95% …”

“…The SSAR's CP values are higher than those obtained for alkyd‐acrylic resins (lower than 94 %) synthesized by miniemulsion polymerization . However, the CP is comparable with those obtained for hyperbranched alkyd‐acrylic resins (between 95.03 and 99.65 %) . In a study of the styrenation of air‐blown linseed oil via reversible addition‐fragmentation chain transfer‐mediated miniemulsion, CP values lower than 78.12 % were obtained …”

“…The residue obtained in this study is comparable with that observed to alkyd‐acrylic resins with the lowest branching degree, whose values were lower than 0.029 wt % . On the other hand, hyperbranched alkyd‐acrylic resins exhibited residues between 7.58 and 39.11 wt % . It can be inferred that the crosslinking carried out by using St and AR to obtain SSARs is lower than that when acrylic monomers (butyl acrylate, methyl methacrylate, and acrylic acid) are used to obtain hyperbranched alkyd‐acrylic resins .…”

“…9 AR or HAR modified with acrylic monomers were obtained by miniemulsion polymerization. 1,10 In the case of HAR, these materials were obtained from hyperbranched polyester polyols (HBP) and unsaturated fatty acids; they can be prepared with low VOCs amount, high gloss, and good adhesion. 6 HAR present higher elasticity, lower viscosity, and lesser drying times than AR.…”

“…1,14 Notably, related studies on the modification of AR with acrylic monomers by free-radical polymerization has been reported with the aim of preparing environmentally friendly materials. 10,15 These materials combine the properties of AR (auto-oxidative curing, high gloss, and penetration in wood) 15 with those of acrylic resins (highly resistant against ultraviolet light, shortest drying time, good film appearance, excellent mechanical properties, and excellent chemical resistance). 13,16 In spite of St being a vinylic monomer as acrylates, which can react with free radicals, it is rarely employed in the modification of AR by miniemulsion polymerization (environmentally friendly).…”