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ABSTRACT 4-Isopropenyl phenol ( 4-IPP) is a versatile dual functional intermediate that can be prepared readily from bisphenol-A ( BPA). Through etherification with epichlorohydrin to the phenolic group of 4-IPP, it can be converted into 4-isopropenyl phenyl glycidyl ether ( IPGE). On further reaction with carbon dioxide in the presence of tetra-n-butyl ammonium bromide ( TBAB) as the catalyst, IPGE was transformed into 4-isopropenylphenoxy propylene carbonate ( IPPC) in 90% yield. Cationic polymerization of IPPC with strong acid such as trifluoromethanesulfonic acid or boron trifluoride diethyl etherate as the catalyst at −40 °C gave a linear poly(isopropenylphenoxy propylene carbonate), poly( IPPC), with multicyclic carbonate groups substituted uniformly at the side-chains of the polymer. The cyclic carbonate groups of poly( IPPC) were further reacted with different aliphatic amines and diamines resulting in formation of polymers with hydroxy-polyurethane on side-chains. Syntheses, characterizations of poly( IPPC) and its conversion into hydroxy-polyurethane crosslinked polymers were presented. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 802-808 [ABSTRACT FROM AUTHOR]

ABSTRACT A diallyl-containing bisphenol, 1,1-bis(3-allyl-4-hydroxyphenyl)-1-(6-oxido-6 H -dibenzo [c,e][1,2] oxaphosphorin-6-yl) ethane ( 1), was prepared by a two-step procedure. Then, a diallyl-containing diamine, 1,1-bis(3-allyl-4-(4-aminophenoxy)-phenyl)-1-(6-oxido-6 H-dibenzo [c,e][1,2] oxaphosphorin-6-yl)ethane ( 3), was prepared from the nucleophilic substitution of ( 1) with 4-fluoronitrobenzene, followed by the reduction by Fe/HCl. A flexible polyimide ( 4) with curable diallyl linkages was prepared from the condensation of ( 3) and 4,4′-oxydiphthalic anhydride in m-cresol in the presence of isoquinoline. Curing polyimide ( 4) at 300 °C leads to thermosetting polyimide ( 5). We discussed the amounts of allyl group on Tg, coefficient of thermal expansion, and thermal stability of thermosetting polyimides, and found that thermal properties and dimensional stability of thermosetting polyimides increase with the amounts of cured allyl moieties. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 513-520 [ABSTRACT FROM AUTHOR]

ABSTRACT A propargyl ether-containing benzoxazine (4) was prepared from a potassium carbonate-catalyzed nucleophilic substitution of propargyl bromide and a phenolic OH-containing benzoxazine (3), which was prepared from 1-(4-hydroxyphenyl)-1-(4-aminophenyl)-1-(6-oxido-6H -dibenz <1,2> oxaphosphorin-6-yl)ethane (1) by a three-step procedure. The curing reactions of (4) were monitored by IR and DSC. A reaction mechanism was proposed based on the observation. Benzoxazines (3) and (4) were applied as epoxy curing agents. The microstructure and the structure-property relationship of the resulting thermosets are discussed. The double-strand structure in (4)-cured epoxy thermosets afforded higher crosslinking density, and led to higher thermal properties. In addition, the (4)-cured epoxy thermosets possess half the amount of highly polar hydroxyl groups than those of the (3)-cured epoxy thermosets, resulting in a lower dielectric constant, dissipation factor, and water absorption. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 1359-1367 [ABSTRACT FROM AUTHOR]

ABSTRACT A new phosphinated acetoxybenzoic acid, 1-(4-acetoxyphenyl)-1-(4-carboxylphenyl)-1-(6-oxido-6H-dibenz<1,2> oxaphosphorin-6-yl)ethane (3), was prepared by a three-step procedure. Phosphinated copolyesters based on the acidolysis and polycondensation of (3) with poly(ethylene terephthalate) (PET) were prepared. The crystallinity of copolyesters decreased gradually with the content of (3), as shown in wide-angle X-ray diffractograms and differential scanning calorimetry thermograms. Dynamic mechanical analysis and thermal mechanical analysis show Tg increased with the content of (3). UL-94 flame retardant test shows that the flame resistance of PET was enhanced with the content of (3), and a copolyester with UL-94 V-0 grade can be achieved with a phosphorus content as low as 1.43 wt %. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 424-434 [ABSTRACT FROM AUTHOR]

ABSTRACT Four novel diamines (9-12) were prepared by a two-step procedure from phosphinated phenols (1-4) that were prepared from acid-fragmentation of four bisphenols, including bisphenol A, 4,4′-isopropylidenebis(2,6-dimethylphenol), cis(4-hydroxyphenyl)cyclohexane, and 9,9′- bis(4-hydroxyphenyl)fluorene, followed by nucleophilic addition of 9,10-dihydro-oxa-10-phosphaphenanthrene-10-oxide (DOPO). Copolyimides based on (9-12)/4,4′-diaminodiphenyl ether (ODA)/dianhydride were prepared. The structure-property relationship on the copolyimides was discussed. Due to the structural similarity, (9)/ODA-based copolyimides were compared with (10)/ODA-based copolyimides, while (11)/ODA-based copolyimides were compared with (12)/ODA-based copolyimides. The dimethyl substitutents cause (10)/ODA-based copolyimides to display higher Tg, modulus, dimensional stability, contact angle, and better solubility than (9)/ODA-based copolyimides. (12)/ODA-based copolyimides that exhibit fluorene moieties display higher Tg and thermal stability, but a lower contact angle and poorer solubility than (11)/ODA-based copolyimides that exhibit cyclohexane moieties. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 390-400 [ABSTRACT FROM AUTHOR]

Generally, protection and deprotection procedures of amino groups are required in preparing propargyl ether-containing benzoxazines. In this study, we report a facile, deprotection-free preparation of a propargyl ether-containing phosphinated benzoxazine (2) from the nucleophilic substitution of a phenolic OH-containing phosphinated benzoxazine (1) and propargyl bromide in the catalysis of potassium carbonate. The structure of (2) was characterized and confirmed by a high-resolution mass spectrum, 1H, 13C, 1H-1H, 1H-13C nuclear magnetic resonance (NMR) spectra, and X-ray single crystal diffractogram. infrared (IR) and differential scanning calorimetry were used to monitor the ring-opening of benzoxazine and crosslinking of propargyl ether. The microstructure and the structure-property relationship of the resulting homopolymers and copolymers are discussed. The Tg of homopolymer of (2) is 208 °C by dynamic mechanical analysis, the coefficient of thermal expansion is 43 ppm/°C, and Td 5% (N2) is 393 °C, respectively, which are higher than those of the homopolymer of (1). Similar trends were observed in the copolymerization system. The results demonstrate the beneficial effect of crosslinking afforded by the propargyl ether group is higher than that by the phenolic OH group. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 [ABSTRACT FROM AUTHOR]

This study focuses on preparing soluble, high- Tg polyetherimides (PEIs) with good flame retardancy. To achieve this goal, a phosphinated aminophenol, 1-(4-hydroxyphenyl)-1-(4-aminophenyl)-1-(6-oxido-6H-dibenz〈c,e〉〈1,2〉oxaphosphorin-6-yl)ethane ( 1), was prepared. Then, an asymmetric etherdiamine, 1-(4-(4-aminophenoxy)phenyl)-1-(4-aminophenyl)-1-(6-oxido-6H-dibenz〈c,e〉〈1,2〉oxaphosphorin-6-yl)ethane ( 3), was prepared from the nucleophilic substitution of ( 1) with 4-chloronitrobenzene, followed by catalytic hydrogenation. Light colored, tough, and foldable PEIs ( 5) with good thermal stability, organo-solubility, and good flame retardancy were synthesized from the condensation of ( 3) with various aromatic dianhydrides in N, N-dimethylacetamide, followed by thermal imidization. Properties of the resulting PEIs were evaluated and compared with those of symmetric PEIs ( 5′) and polyimides ( 5″). The structure-property relationships were discussed. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 [ABSTRACT FROM AUTHOR]