Zeolites are microporous materials with pores and channels of molecular dimensions that find numerous applications in catalysis, separations, ion exchange, etc. However, whereas uniformity of micropore size is a most desirable and enabling characteristic for many of their uses, in certain cases, for example in reactions involving bulky molecules, it is a limitation. For this reason, synthesis of hierarchical zeolites with micro- and mesoporosity is of considerable interest as a way to control molecular traffic for improved catalytic and separation performance. Herein, we report a general synthesis route for the confined synthesis of zeolites within three-dimensionally ordered mesoporous carbon templates by conventional hydrothermal synthesis. Various zeolites, including BEA, LTA, FAU, and LTL, with three-dimensionally ordered mesoporous-imprinted structure have been synthesized by this approach. It is expected that these hierarchical zeolite materials will provide building blocks for thin-film and other syntheses and may provide a basis for quantitatively studying the mass-transfer limitation on the catalytic performance of zeolite catalysts.

Objectives A model BisGMA/TEGDMA unfilled resin was utilized to investigate the effect of varied irradiation intensity on the photopolymerization kinetics and shrinkage stress evolution, as a means for evaluation of the reciprocity relationship. Methods Functional group conversion was determined by FTIR spectroscopy and polymerization shrinkage stress was obtained by a tensometer. Samples were polymerized with UV light from an EXFO Acticure with 0.1 wt% photoinitiator. A one dimensional kinetic model was utilized to predict the conversion-dose relationship. Results As irradiation intensity increased, conversion decreased at a constant irradiation dose and the overall dose required to achieve full conversion increased. Methacrylate conversion ranged from 64 ± 2 % at 3 mW/cm2 to 78 ± 1 % at 24 mW/cm2 while the final shrinkage stress varied from 2.4 ± 0.1 MPa to 3.0 ± 0.1 MPa. The ultimate conversion and shrinkage stress levels achieved were dependent not only upon dose but also the irradiation intensity, in contrast to an idealized reciprocity relationship. A kinetic model was utilized to analyze this behavior and provide theoretical conversion profiles versus irradiation time and dose. Significance Analysis of the experimental and modeling results demonstrated that the polymerization kinetics do not and should not be expected to follow the reciprocity law behavior. As irradiation intensity is increased, the overall dose required to achieve full conversion also increased. Further, the ultimate conversion and shrinkage stress that are achieved are not dependent only upon dose but rather upon the irradiation intensity and corresponding polymerization rate.

c-Oriented AlPO 4 -5 films were synthesized by seeded growth on silicon substrates. Secondary hydrothermal treatment of the seeded substrates under conditions that favor c-out-of-plane growth yielded non-intergrown, highly oriented columnar crystals with a length of 7 µm. Modifying the conditions so that in-plane growth is favored and executing yet another ("tertiary") growth, the crystals obtained by secondary treatment were grown in-plane, along the a-, b-directions, filling the gaps between the columnar grains and yielding well-intergrown, highly oriented, continuous AlPO 4 -5 films. The oriented films obtained by the technique presented here can be potentially useful for separations and catalysis as well as electronic and electrochemical applications.

With the advent of systematically designed controllable reversible addition–fragmentation termination (CRAFT) compounds, we have identified structure–property relationships related to the RAFT compositional structure as it impacts photoplasticity in covalent adaptable networks (CANs). In this study, we have expanded the range and functional capabilities of addition–fragmentation capable network forming monomers by synthesizing and evaluating systematically varying CRAFT monomers with the general formula ABCBA. Subsequent assessment of the impact of these monomers on photoplasticity and stress relaxation was performed. Structural variation of the A and B segments, in particular, imparts increased efficiency and efficacy in stress relaxation and photoplasticity. The CRAFT monomers employed have highly efficient stress relaxation properties demonstrating stress reduction of up to 54% and 75%, respectively, in postpolymerization network photoplasticity experiments. Furthermore, polymerization stress reduction in purely acrylate and acrylate–thiol networks with CRAFT monomers shows a remarkably enhanced efficacy with the inclusion of relatively small amounts of the monomers. With a loading of only 1.5 wt % of the alkene trithiocarbonate monomer in each system more than 75% stress reduction was achieved.