SynopsisPolyimides were synthesized from pyromellitic dianhydride (PMDA), 3,3',4,4'-benzophenone tetracarboxylic dianhydride (BTDA), and three different diamines with the following general structure: R where R is ethyl, propyl, or isobutyl. The poly(amic acids) obtained had inherent viscosities ranging from 0.30 to 0.93 and were thermally/chemically converted to polyimides. The thermal stability of the polyimides was evaluated by using dynamic thermogravimetric analysis in air. Physical and thermal properties of these polyimides were compared with that obtained by reacting 2,2-bis(4aminophenyI) propane and PMDA/BTDA. 1. 2,2-bis(4-aminophenyl) propane (PRDA) 2. 2,2-bis(4-aminophenyl) butane (BUDA) 3. 2,2-bis(4-aminophenyl) pentane (PEDA) 4. 2,2-bis(4-aminophenyl)-4-methylpentane (MPDA) Although the reaction of PRDA with PMDA has been reported previously, the polymer was again synthesized under identical conditions for the comparative study.
Polyamides containing arylene sulfone ether linkages were synthesized from 4,4′‐[sulfonylbis(p‐phenyleneoxy)] dibenzoyl chloride (SPCI), 3,3′‐[sulfonylbis(p‐phenyleneoxy)] dibenzoyl chloride (SMCl), and arylene sulfone ether diamines (SED), by solution and interfacial polymerization techniques. In solution polymerization, the effect of various acid acceptors such as propylene oxide (PO), lithium chloride (LiCl)/lithium hydroxide (LiOH), and triethylamine (TEA) on molecular weight of the polyamides was studied. The effect of methyl substituted and unsubstituted aromatic sulfone ether diamines on molecular weight and thermal properties of polyamides was also studied. The polyamides prepared were characterized by solution viscosity, elemental analysis, thermal gravimetric analysis, differential scanning calorimetry, and x‐ray diffraction. Physical and thermal properties of polyamides prepared from SPCl and SED were compared with the polyamides prepared from SMCl and SED.
SynopsisA number of methyl-substituted bis[(phenyleneoxy) sulfone] dianilines were synthesized and reacted with pyromellitic dianhydride (PMDA), benzophenone tetracarboxylic acid dianhydride (BTDA), terephthaloyl chloride (TPC), isophthaloyl chloride (IPC), and trimellitic anhydride acid chloride (TMAC) to prepare a series of polyimides, polyamides, and poly(amide-imides), respectively. Low temperature solution and interfacial polymerization techniques were utilized to prepare the above polymers. Most of the polymers prepared formed tough, transparent flexible films. The prepared polymers were characterized by solution viscosity, thermal gravimetric analysis (dynamic and isothermal), and differential scanning calorimetry. The effect of the number and the ring substitution of methyl groups on polymer properties is discussed.
A spectrum of newly synthesized polyamides have been characterized with the intent of elucidating crystalline and possible liquid crystalline behavior. The different polymers contained various rotatable linkages in the main chain as well as substituent methyl groups in some cases. These were deemed as important variables for controlling the propensity to form ordered morphologies in these polymers. Methods of characterization included: X‐ray diffraction analysis, differential scanning calorimetry, and optical birefringence.
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