Analysis of dynamic mechanical, thermal and surface properties of poly(urethane-ester-siloxane) networks based on hyperbranched polyester

Surface and thermomechanical characterization of polyurethane networks based on poly(dimethylsiloxane) and hyperbranched polyester

“…The large number of terminal hydroxyl groups present in Boltorn ® HBPs enables fast formation of networks that have good mechanical properties, as well as good resistance to chemicals [11][12][13][14], while the presence of PDMS contributes to the good thermal and surface properties, and to elasticity of the highly crosslinked materials. In our previous studies, we have investigated the influence of the content of !,"-dihydroxyethoxy propyl-poly(dimethylsiloxane) (EO-PDMS) and type of HBPs on the swelling behavior, morphological, thermal and thermomechanical properties of PU networks [15][16][17][18][19][20][21]. These results confirmed that physical and thermal properties are related to the crosslinking density, hydrogen bonding interactions, microphase separation and content of EO-PDMS soft segment.…”

“…Catalyst concentration was kept at 0.02 wt% [25][26][27]. The details for the synthesis of similar PU networks are given in our previously published papers [16][17][18][19][20][21]. Compositions of the synthesized PUs and weights of the reactants used for the synthesis of PUs are presented in Table 1.…”

“…The measurements were carried out using rectangular specimens (15.0 mm&' 7.8 mm&' 1.0 mm±0.2 mm), under torsion mode, using torsion fixture (rectangle) geometry. All details of the calculation of crosslinking density and average molecular weight between two crosslinks using the rubber elasticity theory and calculated from DMTA results, are described in the literature [19][20][21]33]. Some clarification of the calculation of crosslinking density is given.…”

Thermal degradation studies of poly(urethane–siloxane) thermosets based on co-poly(dimethyl)(methyl, 3-glycidoxypropyl)siloxane and epoxy-terminated urethane oligomer

“…However, the investigations on polyurethanes with other siloxane structures including polydimethylsiloxane chains terminated only at one side with two hydroxyl groups [5] or polyhedral oligomeric silsesquioxane (POSS) [8] have been recently developed. The thermal degradation studies were also carried out for poly (urethane-siloxane) networks obtained by sol-gel process [9], by cross-linking with hyperbranched polyester [10], or by moisture curing [11]. Moreover, detailed studies on kinetics of the thermal decomposition of poly(urethane-siloxane) semi-interpenetrating polymer networks (semi-IPNs) [12] and networks based on comb-like structure co-poly(dimethyl)(methyl, hydroxypolyoxyethylenepropyl) siloxane cured with aliphatic diisocyanates [13] have been recently developed.…”

Relationship between structure and aromatic solvent permeability of crosslinked polyurethanes based on hyperbranched polyesters

“…Previous studies in this area have been conducted mainly on conventional polyurethanes synthesized using classical chain extenders or crosslinkers. However, the application of hyperbranched macromolecules as crosslinkers in the synthesis of polyurethanes has attracted a great deal of scientific attention in recent years . Cao and co‐workers showed that a hyperbranched polyurethane (HBPU) copolymer prepared using a hyperbranched polyester (HBPE) as chain extender could be used as a new kind of solid–solid phase change material for thermal energy storage and temperature control .…”