Polymeric hybrid materials have recently attracted great interest due to their advantageous performance relative to the non-hybrid counterparts. Typical hybrid materials contain a compact inorganic phase bonded (often covalently) with an organic phase, which may be phase-segregated or dispersed at a molecular level. Recently, hybrids containing polyhedral oligosilsesquioxanes (POSS) either covalently bonded to or simply dispersed in the polymer matrix have been the subject of increasing attention. This is due to the potentially interesting properties associated with the unique structure of the POSS cage, a nanoparticle with silica-like inorganic core (SiO1.5)n (n = 8, 10, 12) and an outer shell of covalently bonded hydrocarbon or organofunctional groups. These organophilic POSS derivatives can be incorporated into virtually any polymer and, depending on the specific polymer-POSS interaction, provide the polymer matrix with enhanced or new application properties. Copolymerization of monofunctional or multifunctional POSS derivatives is an effective way of achieving a good dispersion of the POSS moieties, and a wide variety of synthetic routes have been proposed, mainly based on solution or melt processing. On the other hand, the synthesis of POSScontaining copolymers by hetherophasic polymerization has received much less attention. We had previously described the first example of the synthesis of hybrid POSS-acrylic copolymer latexes by miniemulsion polymerization.1 In the present investigation the thermal, mechanical and surface properties of the nanocomposite latex films at increasing POSS loadings have been evaluated. Semi-IPN structures were also produced by photopolymerization of monomer-swollen latex films as a means to further investigate the microgel structure and mechanical properties of the material.
Film-Forming Behavior and Material Properties of Hybrid Nanostructured Films from Water-Borne Mono- and Multifunctional POSS Copolymers
CASTELVETRO, VALTER;
2007-01-01
Abstract
Polymeric hybrid materials have recently attracted great interest due to their advantageous performance relative to the non-hybrid counterparts. Typical hybrid materials contain a compact inorganic phase bonded (often covalently) with an organic phase, which may be phase-segregated or dispersed at a molecular level. Recently, hybrids containing polyhedral oligosilsesquioxanes (POSS) either covalently bonded to or simply dispersed in the polymer matrix have been the subject of increasing attention. This is due to the potentially interesting properties associated with the unique structure of the POSS cage, a nanoparticle with silica-like inorganic core (SiO1.5)n (n = 8, 10, 12) and an outer shell of covalently bonded hydrocarbon or organofunctional groups. These organophilic POSS derivatives can be incorporated into virtually any polymer and, depending on the specific polymer-POSS interaction, provide the polymer matrix with enhanced or new application properties. Copolymerization of monofunctional or multifunctional POSS derivatives is an effective way of achieving a good dispersion of the POSS moieties, and a wide variety of synthetic routes have been proposed, mainly based on solution or melt processing. On the other hand, the synthesis of POSScontaining copolymers by hetherophasic polymerization has received much less attention. We had previously described the first example of the synthesis of hybrid POSS-acrylic copolymer latexes by miniemulsion polymerization.1 In the present investigation the thermal, mechanical and surface properties of the nanocomposite latex films at increasing POSS loadings have been evaluated. Semi-IPN structures were also produced by photopolymerization of monomer-swollen latex films as a means to further investigate the microgel structure and mechanical properties of the material.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
