Reference

Polyimide oligomer with terminal acetylene groups

Polyimide oligomer with terminal acetylene groups. Bilow, Norman; Landis, Abraham L. (Hughes Aircraft Co., USA). Ger. Offen. DE 2616691 28 Oct 1976, 28 pp. (German). (Germany). CODEN: GWXXBX. CLASS: IC: C08G073-12. PRIORITY: US 75-571128 24 Apr 1975. DOCUMENT TYPE: Patent CA Section: 35 (Synthetic High Polymers) Section cross-reference(s): 25, 27 The imides I [Z1, Z2 = CH2, (CF2)n, CF2OCF2, (CF3)2C, SO2, O, CO, S] are sol., low-melting compds. with low melt viscosity, useful in the prepn. of polyimides by addn. reactions. Thus, adding 51.4 g 3'-(3-nitrophenoxy)acetophenone [61435-06-1] in 100 ml DMF dropwise to 45.9 g POCl3 in 70 ml DMF stirred at ambient temp. and stirring overnight gives 44.2 g 3-chloro-3-[3-(3-nitrophenoxy)phenyl]-2-propenal (II) [58478-16-3]. Adding 99.6 g II in 265 ml dioxane over 45 min to 27 g NaOH in 265 ml refluxing H2O and refluxing 30 min gives 61.4 g [3-(3-nitrophenoxy)phenyl]acetylene [58478-17-4], redn. of 30.0 g of which with aq. FeSO4 gives 21.1 g [3-(3-aminophenoxy)phenyl]acetylene (III) [56993-37-4]. Refluxing 1.48 g 79% pure III and 0.82 g 4,4'-carbonyldiphthalic anhydride [2421-28-5] in 2 ml DMF 1 h and refluxing the product overnight in 3. 121-71-1 and 585-79-5 which are cas registry numbers of substances are two of reagents here.5 ml C6H6 and 7 ml cresol gives 0.80 g I(Z1 = CO, Z2 = O) [59947-14-7], m. 175-85.degree.. .

On the effect of temperature on the dielectric relaxation time of some benzene derivatives and certain of their binary mixtures

All Rights Reserved. On the effect of temperature on the dielectric relaxation time of some benzene derivatives and certain of their binary mixtures. Vasan, S. T.; Ayachit, Narasimha H.; Deshpande, D. K. (Department of Physics, Rural Engineering College, Hulkoti, India). Physics and Chemistry of Liquids, 44(5), 513-519 (English) 2006 Taylor & Francis Ltd. CODEN: PCLQAC. ISSN: 0031-9104. DOCUMENT TYPE: Journal CA Section: 22 (Physical Organic Chemistry) Dielec. relaxation behavior of polar mols. in a non-polar solvent, or mixts. of these substances at different microwave frequencies and over a range of temps. and concns. give an idea about inter- and intra-mol. forces. Also such studies enable one to calc. thermodn. parameters such as, the change of activation energy for dipole orientation (DG*), the enthalpy (DH*) and entropy (DS*) of activation. Such studies in the case of binary, ternary, etc. mixts. of polar mols. in pure liq. phase or in dil. soln. phase of them in a non-polar solvent help in drawing certain quant. conclusions regarding their relaxation behavior as to whether a single component is responsible for obsd. microwave absorption, or a cooperative phenomenon (av.) by all the dipoles of the mixt. contribute to it. An exptl. investigation is here performed on typical systems. With this in view, systematic dielec.In this experiment, several chemicals are used like 585-79-5 and 459-22-3 measurements in a range of temps. are carried out at a single microwave frequency on a single wt. fraction in benzene of the four substituted phenols, namely, p-fluorophenylacetonitrile, p-bromonitrobenzene, m-bromonitrobenzene and 2-chloro-6-fluorobenzaldehyde and on binary (1:1) mixts. of [2-chloro-6-fluoro-benzaldehyde + o-ethylphenol] and [p-fluorophenylacetonitrile + 2-butylphenol] in benzene as solvent at different temps. The results are presented and discussed. .