Novel ionizable polymer networks were prepared from oligo(ethylene glycol) (OEG) multiacrylates and acrylic acid (AA), employing bulk radical photopolymerization techniques. The properties of these materials exhibit a complex dependence on the network structure and composition. Dynamic mechanical analysis and penetrant sorption experiments demonstrated that the cross-linked structure of the mat...

Microparticles or nanospheres of hydrogels of crosslinked poly(methacrylic acid) grafted with poly(ethylene glycol) as well as crosslinked poly(acrylic acid) grafted with poly(ethylene glycol) were prepared for use as oral insulin delivery carriers. The copolymer carriers were synthesized by precipitation/dispersion polymerization that led to gel nanospheres or by bulk polymerization and subseq...

In thermal frontal polymerization, the interplay between heat diffusion and Arrhenius type reaction kinetics gives rise to a propagating reactive front that is effectively sustained through a system positive feedback mechanism. We seek to understand how spatial confinement affects the system dynamics and overall polymerization kinetics. We find that with increasing confinement of the system, th...

OBJECTIVES The aim of this study was to investigate the effect of layering methods, flowable composite liner and use of low shrinkage silorane-based composite on the polymerization shrinkage stress of light cured composites. METHODS Aluminum blocks were used to prepare MOD cavities and divided into four groups. A universal hybrid methacrylate-based composite (Z250), a flowable composite (Z350...

The physical, mechanical and biological properties of multicomponent acrylate-based hard lenses are directly influenced by degree of conversion achieved during copolymerization. In this research, polyhedral oligomeric silsesquioxane (POSS) acrylate is introduced into the polymer backbone in combination with hydroxyethyl methacrylate, dimethyl itaconate, methyl methacrylate, 3-(trimethoxysilyl) ...

The silica aerogel was prepared by the acid–base sol–gel polymerization of tetraethylorthosilicate precursor followed by ambient pressure drying. The prepared silica aerogels were characterized by Fourier transform infrared )FT-IR(, Thermo-gravimetric and differential thermal analysis )TG/DTA(, X-ray diffractometer )XRD(, Energy dispersive X-ray microanalysis )EDX(, Brunauer–Emmitt–Teller (BET)...

The generation of laterally structured patterns of conju gated, conductive polymers on flat substrates is a key step in the development of new technologies for the production of, for example, displays or low cost flexible circuits. Printing and related procedures, in which the pattern of the individual pieces produced can also differ from one another, are patterning techniques suited for mass p...

A method of radiation dosimetry is described which is based on the radiation-induced initiation of polymerization of a bulk monomer (e.g. methyl methacrylate) containing a small concentration (about 100 ppm) of a compound which is non-fluorescent but which becomes highly fluorescent when it is incorporated into a growing polymer chain of the bulk monomer. We call the overall process 'radio-fluo...

The contraction stress generated during the photopolymerization of resin dental composites is the major disadvantage. The water sorption in the oral environment should counteract the contraction stress. The purpose was to evaluate the influence of the water sorption of composite materials on polymerization shrinkage stress generated at the restoration-tooth interface. The following materials we...

This study investigated the influence of modulated photo-activation on axial polymerization shrinkage, shrinkage force, and hardening of light- and dual-curing resin-based composites. Three light-curing resin composites (SDR bulk-fill, Esthet X flow, and Esthet X HD) and one dual-curing material (Rebilda DC) were subjected to different irradiation protocols with identical energy density (27 J c...