Poly methyl swelling resistance

Many poly(methyl methacrylate)-based denture teeth are based on a specialized interpenetrating polymer network technology (90,91). First, densely cross-linked suspension-polymerized particles are prepared. These are then placed in a similar monomer mix (with appropriate inorganic materials, etc.), and the mix re-polymerized. Because they are highly cross-linked, they are more abrasion resistant, as described above, ffowever, they swell less in the presence of triglycerides such as butter, salad oU, fats, and similar materials which swell and damage uncross-linked poly(methyl methacrylate)-based teeth. 

The need for HTPs or HTPBs is often for chemical (e.g., preventing of swelling or oxidation) and mechanical performance. For example, in the petroleum industry dual-layer hollow fiber membranes are used for separation of H2/CO2 and CO2/CH4 gases. These are prepared from solutions of 1 1 PIB/PI blend (e.g. poly[2,2 -(l,3-phenylene)-5,5 -bibenzimidazole] and poly[3,3 4,4 -benzophenone-icira-carboxylic-df-anhydride-co-5(6)-amino-l-(4 -amino-phenyl-l,3-/n-methyl-indane)]).i i The spun hollow fibers are coated by a solution of silicone rubber. The membranes had the desired microstructure. Membrane selectivity of 11.11 and 41.81 was obtained for H2/ CO2 and CO2/CH4, respectively. Furthermore, the new membranes showed good resistance toward COj-induced plasticization. Camacho-Zuniga et al. 

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