Diluents polymethacrylates

The pore size, the pore-size distribution, and the surface area of organic polymeric supports can be controlled easily during production by precipitation processes that take place during the conversion of liquid microdroplets to solid microbeads. For example, polystyrene beads produced without cross-linked agents or diluent are nonporous or contain very small pores. However, by using bigb divinylbenzene (DVB) concentrations and monomer diluents, polymer beads with wide porosities and pore sizes can be produced, depending on the proportion of DVB and monomer diluent. Control of porosity by means of monomer diluent has been extensively studied for polystyrene (3-6) and polymethacrylate (7-10). 

The relaxation process due to the motion of the side groups is transformed15,146 I48) by diluents into the /9d process in a way formally resembling that operative in the preceding case. The corresponding motional unit probably consists148 of die group R and diluent molecule(s). Data obtained for polymethacrylates, which so far appear to be the most complete, are discussed in Sect. 5.3. 

Most conspicuous modifications of the dynamic mechanical response spectra of PHEMA and related polymers are brought about by incorporation of low-molecular weight compounds (Fig. 13). Along with alterations of parameters (temperature, height, shape) of the peaks characteristic of a dry polymer, usually a new diluent peak appears. (The relaxation patterns of various polymethacrylates are not modified by diluents in a unique way but several modes can be distinguished as mentioned before.) A remarkable feature... 

The acrylate or methacrylate functional PIBs have also been used in UV-curable solventless coatings formulation in the presence of reactive diluents (multifunctional acrylate or methacrylate esters) and a UV-sensitizer [104]. The products were transparent, flexible films, with very little extractables, in which hard polyacrylate or polymethacrylate domains were dispersed in the soft PIB matrix. Tensile strength and ultimate elongation have also been obtained. 

Polymethacrylates —CO—O— Eilm former, tablet binder and diluent, sustained release polymer in right combinations... 

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