Browsing by Author "Tseng, FP"

Now showing 1 - 12 of 12

Electrostatic dissipation and flexibility of poly(oxyalkylene)amine segmented epoxy derivatives
(2000-04-01)
Lin, JJ
;
Tseng, FP
;
Chang, FC
;
應用化學系
;
Department of Applied Chemistry
A family of hydrophilic and flexible epoxy polymers was prepared from the reaction of poly(oxyalkylene)amines and diglycidyl ether of bisphenol-A (DGEBA) at 1:1 molar ratio of N-H to epoxide. The use of a high molecular weight (M-W = 1000-6000) poly(oxyethylene-oxypropylene)amine and a low M-W amine as curing agents provided epoxy materials with good properties in toughness and hydrophilicity. The hydrophilicity, probed by surface resistivity of these cured materials, was found to be affected by the nature and weight content of poly(oxyethylene) segment in the polymer backbone, and also by the degree of crystallinity. Specifically, in the presence of a water-soluble poly(oxyethylene-oxypropylene)diamine of M-W 2000 the cured epoxies can reach surface resistivity as low as 10(8.6-9.6) Omega/square. In comparison, the water-insoluble poly(oxypropylene) diamine of M-W 2000 afforded a higher surface resistivity of 10(10.5) Omega/square because of the difference in hydrophilicity between oxyethylene and oxypropylene functionalities. Poly(oxypropylene)diamine of M-W 230 as the sole curing agent generated an epoxy with even higher surface resistivity of 10(13) Omega/square due to a highly crosslinking structure. With proper selection of mixed poly(oxyethylene-oxypropylene)diamine (25 wt%) and 2-aminoethanol (9 wt%), the DGEBA cured polymer had an appropriate surface resistivity of 10(9.8) Omega/square for antistatics. Moreover, this material was extremely ductile in appearance and showed over 500% elongation at break during mechanical tests. The high flexibility is rationalized by the balanced chemical structure of poly(oxyalkylene) segments and bisphenol-A distributed in a slightly crosslinked system. (C) 2000 Society of Chemical Industry.
Phase behaviors of poly(oxyethylene)-grafted polypropylene copolymers
(2000-03-01)
Lin, JJ
;
Shau, SM
;
Tseng, FP
;
Chang, FC
;
應用化學系
A family of amphiphilic graft copolymers were prepared from a maleated polypropylene (PP-g-MA) and various crystalline poly(oxyethylene)-segmented amines of 1000 to 3000 molecular weight. Structurally, these copolymers consist of polypropylene (PP) backbone and several crystalline poly(oxyethylene) (POE) pendants in the structure. In the observation of their phase behaviors by using a differential scanning calorimeter (DSC), the interference between the POE segments and PP backbone was found. In a particular case (PP-g-MA/ED-2001), the heat of POE crystallization did not show off in the cooling curve of the DSC, but appeared during the consecutive heating process. Generally, heating and cooling patterns of the DSC analyses showed the shifts of melting and crystallizing temperatures, depending on the length and the termini of POE, from those of the starting materials- PP-g-MA and POE amines. The TGA and optical microscopy observation further supported the DSC analyses.
Poly(oxypropylene)-amide grafted polypropylene as novel compatibilizer for PP and PA6 blends
(2001-01-01)
Tseng, FP
;
Lin, JJ
;
Tseng, CR
;
Chang, FC
;
應用化學系
Poly(oxypropylene)-amide grafted polypropylene (PP) was prepared in an extruder by the reaction of poly(oxypropylene) (POP)diamines and maleated PP (PP-g-MA). The resulting POP-grafted PP copolymers are confirmed by the FTIR analysis, and used as compatibilizers for polyamide 6 (PA6) and polypropylene blends, These compatibilizers, POP-functionalized PPs (PP-g-MA-co-POPs), have different amphiphilic properties depending on the content of MA in the starting PP-g-MA and the molar ratio of MA/amine. The compatibilization effect is examined in terms of morphologies, thermal and mechanical properties. The morphologies, affected by the molecular weight of POP diamine in PP-g-MA-co-POP copolymer, show a decreasing size of the dispersed PA6 particles as the molecular weight of POP diamine increasing from 230 to 400 to 2000. Using these PP-g-MA-co-POP copolymers, the compatibilized blends show improvements in mechanical properties, including Izod impact strength and tensile toughness, over a conventional compatibilizer. The POP and amide functionalities in the compatibilizers can facilitate the formation of hydrogen bonding with PA6 and, therefore, the compatibilizing effect. During the compounding process, the compatibilizers further react with PA6 in situ to afford the mixture of PP-g-MA-co-POP-PA6, PP-g-MA-co-POP-co-PA6 and PP-g-MA-co-PA6 copolymers, which further improves the compatibilizing effect. (C) 2000 Elsevier Science Ltd. All rights reserved.
Poly(oxypropylene)-amide grafted polypropylene as novel compatibilizer for PP and PA6 blends (vol 42, pg 713, 2001)
(2001-05-01)
Tseng, FP
;
Lin, JJ
;
Tseng, CR
;
Chang, FC
;
應用化學系
PP/PA6 blends compatibilized by poly(oxypropylene)amide-functionalized PP.
(1999-08-22)
Lin, JJ
;
Young, MY
;
Tseng, FP
;
Chang, FC
;
應用化學系
Preparation and epoxy curing of novel dicyclopentadiene-derived Mannich amines
(1999-03-28)
Tseng, FP
;
Chang, FC
;
Lin, SF
;
Lin, JJ
;
應用化學系
Phenol/dicyclopentadiene (DCPD) adducts were prepared from the BF3-catalyzed reaction of p-nonylphenol and dicyclopentadiene at molar ratios of 2 : 1 and 3 : 2. The phenol-terminating adducts were consequently reacted with diethylenetriamine and formaldehyde using Mannich reaction conditions. These products containing phenol, amine and tricyclodecane functionalities in the same molecule can be used as epoxy curing agents. The diethylenetriamine was add to the phenol via Mannich reaction at approximately 50% theoretical equivalent. The multiple N-H soups in amines and the O-H groups in phenols provide crosslinking sites for epoxy resins. The cured epoxy resins show improvement in tensile strength and elongation in comparison with those cured by the poly(oxypropylene) diamine (400 molecular weight) or diethylenetriamine. (C) 1999 John Wiley & Sons, Inc.
Preparation and epoxy curing of novel dicyclopentadiene-derived Mannich amines
(1997-09-07)
Lin, JJ
;
Lin, SF
;
Chang, FC
;
Tseng, FP
;
應用化學系
Preparation and epoxy curing of novel dicyclopentadiene-derived Mannich amines
(1997-09-07)
Lin, JJ
;
Lin, SF
;
Chang, FC
;
Tseng, FP
;
應用化學系
Preparation and epoxy curing of novel Mannich bases.
(1999-08-22)
Lin, JJ
;
Lin, SF
;
Tseng, FP
;
Chang, FC
;
應用化學系
Preparation and epoxy curing of p-nonylphenol/dicyclopentadiene adducts
(1999-11-28)
Tseng, FP
;
Chang, FC
;
Lin, SF
;
Lin, JJ
;
應用化學系
Phenol/dicyclopentadiene adducts were prepared from the BF3-catalyzed reaction of p-nonylphenol and dicyclopentadiene at molar ratios of 2 : 1 and 3 : 2. These dicyclopentadiene-derived novolac products contain tricyclodecane and multiple phenol functionalities. In curing with diglycidyl ether of bisphenol A, the polymer properties were compared with those cured with formaldehyde novolac or Jeffamine D-400 amine. When p-nonylphenol/dicyclopentadiene adducts were mixed with other commercially available curing agents such as Jeffamine D-400 amine, the tricyclodecane functionality was introduced into the resulting epoxy network. The flexibility of the cured resin was improved due to the presence of the tricyclodecane moiety in the polymer structure. (C) 1999 John Wiley & Sons, Inc.
Synthesis and epoxy curing of Mannich bases derived from bisphenol A and poly(oxyalkylene)diamine
(2000-10-17)
Lin, JJ
;
Lin, SF
;
Kuo, TT
;
Chang, FC
;
Tseng, FP
A family of Mannich bases were prepared from the reaction of 2,2-bis-(4-hydroxyphenyl)propane (bisphenol A or BPA), formaldehyde, and poly(oxyalkylene)diamines at 1 : 1 : 1 or 1 : 2 : 2 molar ratio. By varying the molar ratio of bisphenol A to amine and the chemical structures of poly(oxyalkylene)diamines, a series of products with multiple functionalities of primary/secondary amines, phenols, and poly(oxyalkylene) were prepared. The curing profiles of these products toward the diglycidyl ether of bisphenol A (DGEBA) were examined by a differential scanning calorimeter (DSC). The physical properties of these cured materials were correlated with the chemical structures of the Mannich bases. Compared with the poly(oxyalkylene)diamines, the built-in phenol moiety in Mannich bases accelerated the curing rate. Both amine and phenol functionalities could be reactive sites toward diglycidyl ethers in a step-wise fashion under catalytic (triphenylphosphine) and different temperature conditions. Furthermore, the cured polymers demonstrated improved properties including tensile and flexural strength in comparison with those cured by the corresponding poly(oxyalkylene)diamines. (C) 2000 John Wiley & Sons, Inc.
Synthesis, characterization and electrostatic dissipating ability of poly(oxyethylene) block polyesteramides
(1999-10-01)
Lin, JJ
;
Sheen, YC
;
Tseng, FP
;
Chang, FC
;
應用化學系
Poly(oxyethylene)diamines were included in the copolymerization of ethylene glycol and dicarboxylic acids, such as terephthalic, adipic and sebacic acid, to produce a series of hydrophilic polyether-ester-amides. With the addition of poly(oxyethylene)diamines (average molecular weight of 2,000) to PET in the amounts of 3.2, 6.6, 12 and 16 wt%, melting points of these polymers dropped accordingly, from 240 degrees C to around 227 degrees C, and the electronic resistivity decreased from 1x10(13) to approximately 8x10(8) ohm/sq. For comparison, the introduction of hydrophilic PEG-2000 or a low molecular weight diamine, such as triethyleneglycol diamine, has less effect on electronic resistivity. Molecular weight. polymer rigidity and ageing are other factors affecting the surface resistivity. The degree of hydrophilicity was measured by the moisture absorption of the fibers made from these polyether-ester-amides. A weight gain of 0.96% was observed for 12 wt% Poly(oxyethylene)diamine modified polyether-ester-amides in comparison with 0.40% for the unmodified poly(ethylene terephthalate), These results are explained by a mechanism involving moisture absorption on the polymer surface through the formation of hydrogen bonding with amide and -(OCH2CH2)-functionalities on the polymer surface.