Photopolymerization compositions

Transition from the differential characteristics p(x, t) and dp(x, f)/df to experimentally determined, that is, averaged on the photopolymerization composition layer, P(t) and dP(f)/dt are calculated via integral transformations of equation (4.42) according to equation (4.43). 

The proposed microheterogeneous model (see equation 5.1) for thermal polymerization needs modification, It is necessary to take into account the presence of a light gradient in the layer of the photopolymerization composition, gradients in the concentrations of the photoinitiator of the oligomer and the depth of the photopolymerization. That is why in this variant of the photoinitiated polymerization equation (5.1) should be written as a partial derivative [8] ... 

Third, taking into account that the thickness of layer I of the photopolymerization composition and its optical density ecal are small in our experiments, let us assume, that the obtained kinetic models will be approximately adequate in the variant of the photoinitiated polymerization in the case when we do not use the differential rate of the photoinitiator decomposition according to equation (6.51), but an average one upon the layer. Under the definition of average values in equation (6.51), we obtain... 

Addition of aluminum powder was not effective this probably is related to the increasing optical density of the photopolymerization composition layer as a results of the lower rate the polymerization process near the metallic surfaces as compared to the polymerization in the volume. As a result, the monolayer near a surfece is weakta- and the explosion proceeds in the place of a fnetal -polymer contact. 

A perfectly ordered polymer composite by four-centre-type photopolymerization of a molecular complex 166... 

A PERFECTLY ORDERED POLYMER COMPOSITE BY FOUR-CENTRE-TYPE PHOTOPOLYMERIZATION OF A MOLECULAR COMPLEX... 

Photopolymerizations of Vinyl Ester Glass Fiber Composites... 

Studies were performed to demonstrate the effects of process variables such as light intensity, cure time, initiator concentration, and fiber loading on the evolution of the mechanical properties of the polymers and composites. Even with moderate incident light intensities (less than 500 mW/cm2) and high fiber loadings (60 wt.% random fibers) the photopolymerizations proceed to completion in minutes and exhibit mechanical properties equivalent to samples prepared by traditional... 

Ranby and Shi also studied hyperbranched methacrylated polyesters and their use in photopolymerizations of films and fiber-reinforced polymer composites. The resins were found to have low viscosities and higher curing rates than those of corresponding linear unsaturated polyesters [131-133]. 

We chose to modify the anhydride monomers with photopolymerizable methacrylate functionalities. Methacrylate-based polymers have a long history in biomedical applications, ranging from photocured dental composites [20] to thermally cured bone cements [21]. Furthermore, photopolymerizations provide many advantages for material handling and processing, including spatial and temporal control of the polymerization and rapid rates at ambient temperatures. Liquid or putty-like monomer/initiator... 

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