Dodecylmethacrylate DMA

Characterization of Monomers and Polymers. Phase transitions of monomers were determined by means of Differential Scanning Caloimetry (DSC) using the Perkin Elmer Dl C IB and thermal polarizing microscopy. 

X-ray studies on the samples were performed with a Rigaku wide angle diffractometer (SG 7B) as well as with a low angle Warhus camera. Cu-K, radiation was used. 

The sharpness s of the low angle x-ray diffraction peaks is defined as the ratio of the peak height h to the width w at 1/2 h. The position of the low angle peak for the cholesteryImethacrylate was found at 20=2.50 a value somewhat higher than the value 20=2. + found for the same polymer in an earlier study (17). 

The glass transition temperatures were estimated from deformation tests performed on the very same pellets which were used for x-ray studies. The tests were made by means of a Perkin-Elmer Thermomechanical analyzer TMS-l, calibrated with polystyrene and polymethylmethacrylate. C-13 NMR Spectra were run in deu-terated chloroform at 10wt% concentration and at 450C. A JEOL PFT-100 spectrometer was used (resolution  

22 Hz pulse width IS sec repetition l.Osec). Tacticity assignments were made from the analysis of the carbonyl portion of the spectrum. 

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