Polyurethane‐block‐polystyrene Prepared by Polymerization in Miniemulsion

Abstract

Waterborne polyurethane‐block‐polystyrene latexes were prepared by miniemulsion polymerization in a single batch. A direct miniemulsion of the monomers mixture containing styrene, IPDI, 2,4‐diethyl‐1,5‐pentanediol and a diol‐functionalized azoinitiator was prepared in water. The polyaddition reaction of the PU was then performed in a first step at room temperature, with the help of the catalysts mixture DBTDL/DMDA, yielding a PU macroazoinitiator. In a second step, the miniemulsion was heated to 72 °C to start the radical polymerization of styrene from the macroazoinitiator chains. The polymers obtained from the miniemulsion were fractionated and each fraction was analyzed by GPC, DSC and 1H NMR spectroscopy. It was shown that 45% of a (linear) copolymer consisting of a PU and PS was obtained, which is a good compatibilizer for PU/PS polymer blends. TEM from the polymer particles in miniemulsion revealed a homogeneous structure inside the particles.magnified image

Miniemulsion Polymerization and the Structure of Polymer and Hybrid Nanoparticles

“…A suppression of the phase separation within polyurethane–polystyrene nanoparticles could be obtained by synthesizing waterborne poly(urethane‐ block ‐styrene) latexes in an miniemulsion polymerization in only one batch 115. A direct miniemulsion of the monomer mixture containing styrene, isophorone diisocyanate, 2,4‐diethyl‐1,5‐pentanediol, and a diol‐functionalized azoinitiator was prepared in water.…”

Simultaneous ROMP and ATRP in Aqueous Dispersed Media: A Straightforward Strategy to Prepare Polymer Composite Particles with Original Morphologies

“…Table 2 summarizes some tests performed following this approach for the synthesis of homopolymer binary blend particles and graft-copolymer particles. The particle yields and overall conversions given for each situation were measured gravimetrically and correspond to overall values: no piece of information is given about the conversion of each monomer (for entries [3][4][5]. Thus, the prepared polymers were analyzed quantitatively by For entries 3-5, the accordance of the obtained values with the initial ratio of the monomer mixture indicated conservation of the composition of the polymer.…”

Miniemulsionspolymerisation und Struktur von Polymer‐ und Hybridnanopartikeln

“…Eine Unterdrückung der Phasentrennung in Polyurethan‐Polystyrol‐Nanopartikeln kann durch die Synthese von wasserbasierten Poly(urethan‐ block ‐styrol)‐Latices in einer Miniemulsionspolymerisation in nur einem Schritt erreicht werden 115. Zunächst wird eine direkte Miniemulsion der Monomermischung aus Styrol, Isophorondiisocyanat, 2,4‐Diethyl‐1,5‐pentandiol und einem Diol‐funktionalisierten Azoinitiator in Wasser vorbereitet.…”