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SYNOPSISThe relationship of the glass transition temperature, T,, to fractional conversion, x , for the conversion of the cyclohexylmethyl ester of the benzophenone tetracarboxylic dianhydride-oxydianiline polyamic acid to polyimide has been investigated using dynamic mechanical analysis (torsion pendulum, TBA) . The glass transition temperature and conversion measurements were obtained on a single solvent-free polyamic acid ester specimen during cooling after heating to successively higher cure temperatures. Conversion was determined from the intensity of a sub-T, mechanical relaxation peak that has been assigned to a relaxation of the cyclohexyl group. The resulting T, versus x relationship is nonlinear. The T, versus x relationship is adequately modeled using an expression derived by Couchman.

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SYNOPSISAn investigation of the kinetics of the thermal elimination of isobutene from the meta and para isomers of the tert-butyl diesters of pyromellitic acid has been carried out using Fourier transform-%man spectroscopy and mass spectroscopy. These studies indicate that the elimination of the tert-butyl group occurs at a temperature 26°C lower for the meta isomer than for the para isomer; the maximum rate of elimination occurs at 184°C for the former and at 210°C for the latter. Analysis of the Raman spectra of the compounds indicates that this effect results from the better packing arrangement in the para monomer compared with the meta monomer. Formation of pyromellitic dianhydride in the tert-butyl diesters of pyromellitic acid occurred only after formation of the pyromellitic acid; thus it occurred at lower temperatures for the meta isomer. When the meta and para tert-butyl diesters of pyromellitic acid are dissolved at 1% concentration in poly (vinyl acetate), the elimination of isobutene occurs at 173°C for both isomers, indicating that it is the differences in crystal packing which give rise to the 26°C difference in the solid-state samples. For the meta, para, and 50/50 mixed isomers of the tert-butyl esters of oxydianiline/pyromellitic dianhydride polyamic acid, the elimination of the tert-butyl group occurs at the same temperature ( 177°C). This result indicates that the packing arrangement of the tert-butyl group is disrupted in the polymer chain, so that intermolecular bonding does not hinder thermal deprotection of the tert-butyl group from the polymer. 0 1992 John Wiley & Sons, Inc. Keywords: polyamic acid esters, thermal elimination of isobutene from pyromellitic acid, meta and para di-tert-butyl esters, thermal elimination of isobutene from thermal elimination of isobutene from monomers of polyamic acid ester

A new series of x-substituted-2-nitrobenzyl arylsulfonate photo-acid generators (PAG) was synthesized. A study ofthe thermal stability ofthe PAG's upon varying the a-substituent was done. The thermal stability was evaluated because there is a correlation between the PAG thermal stability and the post-exposure bake (PEB) temperature tolerance of resists formulated with 2-nitrobenzyl arylsulfonate PAGs and t-BOC polymers. The best thermal stabilities were obtained by having a bulky electron withdrawing group situated at both the 0-and a-positions ofthe 2-nitrobenzyl chromophore. This substitution pattern enhances the thermal stability by suppressing the nucleophilic displacement ofthe sulfonate group by the 2-nitro group oxygen. Increasing the electron withdrawing ability ofthe a-substituent decreased the quantum yield for the photogeneration ofacid from the 2-nitrobenzyl chromophore. However, one of these a-substituents, a-alkoxycarbonyl, was found to give PAG's with optimum thermal stability and quantum yield. These chromophores were used to synthesize PAG's based on strong arylsulfonic acids. The PAGs protected with these new chromophores allow for a higher PEB tolerance, in poly(4-(t-butyoxycarbonyloxy)styrene-sulfone) based resists, than was possible with the 2-(trifluoromethyl)-6-nitrobenzyl chromophore. It was possible to resolve small features (0.35 tm) with a PEB at I 3 5°C with PAG's based on this new chromophore . In contrast, formulations based on a 2-(trifluoromethyl)-6-nitrobenzyl PAG ofthe same acid do not have this resolution at 1 3 5°C because of poor thermal stability.

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ObjectivesThis study aims to determine the proportion of initial cardiometabolic assessment and its predicting factors in adults with schizophrenia, bipolar disorder or other related diagnoses for whom a second-generation antipsychotic was prescribed in the hospital setting.DesignCross-sectional study.SettingThe psychiatry unit of a Canadian tertiary care teaching hospital in Montreal, Canada.Participants402 patients with aforementioned disorders who initiated, restarted or switched to one of the following antipsychotics: clozapine, olanzapine, risperidone, paliperidone or quetiapine, between 2013 and 2016.Primary outcome measuresWe assessed the proportion of cardiometabolic parameters monitored.Secondary outcome measuresWe identified predictors that influence the monitoring of cardiometabolic parameters and we assessed the proportion of adequate interventions following the screening of uncontrolled blood pressure and fasting glucose or glycated haemoglobin (HbA1c) results.ResultsOnly 37.3% of patients received monitoring for at least three cardiometabolic parameters. Blood pressure was assessed in 99.8% of patients; lipid profile in 24.4%; fasting glucose or HbA1c in 33.3% and weight or body mass index in 97.8% of patients while waist circumference was assessed in 4.5% of patients. For patients with abnormal blood pressure and glycaemic values, 42.3% and 41.2% subsequent interventions were done, respectively. The study highlighted the psychiatric diagnosis (substance induced disorder OR 0.06 95% CI 0.00 to 0.44), the presence of a court-ordered treatment (OR 0.79 95% CI 0.35 to 1.79) and the treating psychiatrist (up to OR 34.0 95% CI 16.2 to 140.7) as predictors of cardiometabolic monitoring.ConclusionsThis study reports suboptimal baseline cardiometabolic monitoring of patients taking an antipsychotic in a Canadian hospital. Optimising collaboration within a multidisciplinary team may increase cardiometabolic monitoring.