Continuous-distribution kinetics was applied to thermal degradation of novolac polymer in tetralin. Molecular-weight distributions (MWDs) of novolac polymer and its degradation products were analyzed by HPLC-GPC. Kinetic parameters of the novolac degradation were obtained from the degradation rates, which is defined as the time-dependent changes of the molar concentrations (zeroth moments of the MWDs) of novolac polymer. The calibration curve for molecular weights (MWs) of novolac polymer was determined by analyzing the polymer with a light-scattering detector and a mass spectrometer rather than the use of polystyrene standards in GPC analysis. The continuous-distribution kinetics gave the apparent kinetic parameters of overall reactions of novolac polymer. The kinetic parameters of the degradation of the novolac resin were the pre-exponential factor of 106min-1 and the activation energy of 96 kJ/mol.
Solar ultraviolet radiation was monitored by a UV radiometer: EPPLEY TUVR, which is used commonly around the world, at exposure site in Tsukuba for a year. Daily amount of solar UV radiation (285-395nm) were expressed as a function of daily amount of radiation (305-2800nm) and solar elevation angle at solar noon. Introducing the observed solar radiation at 66 points around Japan for 1976-1990, the yearly total of solar UV dose was obtained and plotted on the map. In order to be referred in the studies of polymeric materials exposed outdoors both in Japan and other areas, daily/monthly data were compiled in the database to be accessed from the personal computer systems.
The thermal destruction process of various zeolites, such as MFI type silicalite, FAU type silicalite, CuZSM-5 and AlPO4-5, depending on the change of temperature was investigated by means of the molecular dynamics (MD) method and computer graphic technique. From the result of MD simulation, the mobilities of Si and O atoms in the framework of MFI type silicalite were found to increase with an increase of temper ature. Finally the framework was destroyed and transformed to an amorphous phase. The destruction process of FAU type silicalite was also investigated. It was found that the heat-resistance of FAU type silicalite is inferior to that of MFI type silicalite. CuZSM-5 was employed in order to investigate the role of ion-exchange cation in the thermal destruction process of zeolite. The framework destruction may proceed mainly through dealumination caused by Cu+ ion access. The framework destruction process of AlPO4-5 was also found to proceed by repeating cleavage and regeneration of Al-O bond in the framework, whose binding energy was weaker than that of the P-O bond.