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1986 Volume 4 Issue 4
1986, 4(4): 297-302
Abstract:
Polyvinyl alcohol carriers bearing active amide and active ester groups were prepared by acetaliza-tion of granular macro-reticular water-insolub1e PVA with glyoxylic acid or p-formylbenzoic acidand further activation reaction with benzotriazole or N-hydroxysuccinimide using DCCI as con-densation agent. The active amides or active esters obtained were easy to react with amines suchas n-butylamine or proteins under mild condition. Ovomucoid, an inhibitor of trypsin was immo-bilized on the above-obtained reactive PVA carrier to give effective affinity adsorbent for the separation or purification of trypsin.
Polyvinyl alcohol carriers bearing active amide and active ester groups were prepared by acetaliza-tion of granular macro-reticular water-insolub1e PVA with glyoxylic acid or p-formylbenzoic acidand further activation reaction with benzotriazole or N-hydroxysuccinimide using DCCI as con-densation agent. The active amides or active esters obtained were easy to react with amines suchas n-butylamine or proteins under mild condition. Ovomucoid, an inhibitor of trypsin was immo-bilized on the above-obtained reactive PVA carrier to give effective affinity adsorbent for the separation or purification of trypsin.
1986, 4(4): 303-308
Abstract:
Block polymer of alternating copolymers, poly[(ST-a-MA)-b(IP-a-MMA)-b-(ST-a-MA)](I), has been synthesized in the presence of AlEt1.5Cl1.5,by using Mn2(CO)10/CBr4. initiation system.The GPC results indicate that there is no unreacted prepolymer in I purified by precipitation andfractionation. The study of NMR shows that every block of polymer I has alternating structure. The dynamicmechanical properties of I measured by torsional braid method indicate that the polymer has two Tg s,being 38 and 75℃,respectively.The transmission electron micrographs of I show they have two phase structure and the domain size increases with increasing molecular weight of hard block.
Block polymer of alternating copolymers, poly[(ST-a-MA)-b(IP-a-MMA)-b-(ST-a-MA)](I), has been synthesized in the presence of AlEt1.5Cl1.5,by using Mn2(CO)10/CBr4. initiation system.The GPC results indicate that there is no unreacted prepolymer in I purified by precipitation andfractionation. The study of NMR shows that every block of polymer I has alternating structure. The dynamicmechanical properties of I measured by torsional braid method indicate that the polymer has two Tg s,being 38 and 75℃,respectively.The transmission electron micrographs of I show they have two phase structure and the domain size increases with increasing molecular weight of hard block.
1986, 4(4): 309-315
Abstract:
A novel highly active catalyst of TiCl4/MgCl2--Al(C2H5), system (called SN-1 catalyst, in whichrare earth compound NdCl3, is included) was used for studying stereospecific polymerization of styrenein benzene solution. Highly isotactic polystyrene was prepared with far better yield and higher cataly-tic efficiency than the results ever reported in literatures. The influences of concentration of mono-mer, catalyst, triethyaluminum as well as polymerization temperature on the catalytic efficiency, yield,tacticity and molecular weight of polystyrene have been investigated.
A novel highly active catalyst of TiCl4/MgCl2--Al(C2H5), system (called SN-1 catalyst, in whichrare earth compound NdCl3, is included) was used for studying stereospecific polymerization of styrenein benzene solution. Highly isotactic polystyrene was prepared with far better yield and higher cataly-tic efficiency than the results ever reported in literatures. The influences of concentration of mono-mer, catalyst, triethyaluminum as well as polymerization temperature on the catalytic efficiency, yield,tacticity and molecular weight of polystyrene have been investigated.
1986, 4(4): 316-321
Abstract:
Seven new polyphosphates containing both nucleic acid base and nitrogen mustard were preparedby reacting the monomers, i.e. 1,3-dihydroxyalkyl-5-fluorouracil(IIa.,b, g), 1,3-dihydroxyalkyluracil(IIc,d) and 1, 3-dihydroxyalkylthymine (IIe,f) with W, N,N-bis(2-chloroethyl)phosphoramide dichlo-ride (I). The monomers and polymers were characterized by 1H-NMR, IR spectra and elementalanalysis. All of the polymers obtained are soluble in water. The antitumor activity of some of thesepolymers were tested against Ehrlish Ascites in mice.The results showed that the polyphosphates containing both 5-fluorouracil and nitrogen mustard exhibit lower toxicity and higher antitumor activity.The inhibition ratio of the polymer(Ⅲa) is 66%.
Seven new polyphosphates containing both nucleic acid base and nitrogen mustard were preparedby reacting the monomers, i.e. 1,3-dihydroxyalkyl-5-fluorouracil(IIa.,b, g), 1,3-dihydroxyalkyluracil(IIc,d) and 1, 3-dihydroxyalkylthymine (IIe,f) with W, N,N-bis(2-chloroethyl)phosphoramide dichlo-ride (I). The monomers and polymers were characterized by 1H-NMR, IR spectra and elementalanalysis. All of the polymers obtained are soluble in water. The antitumor activity of some of thesepolymers were tested against Ehrlish Ascites in mice.The results showed that the polyphosphates containing both 5-fluorouracil and nitrogen mustard exhibit lower toxicity and higher antitumor activity.The inhibition ratio of the polymer(Ⅲa) is 66%.
1986, 4(4): 322-335
Abstract:
The fine structures, paracrystal, porous and phase structures of blend acrylic fibers have bencharacterized using techniques based on X-ray diffraction, gas adsorption, density, electron and opticalmicroscopy, mercury penetration method and IR spectroscopic analysis. The existence of a fibril-void structure, with voids and fibrils of the order of 102.to 103A diameter has been confirmed for thewet-spun blend fibers. It was found that the blend acrylic fiber in the present work is a kind of ma-trix-fibril fiber;phase separation takes place in it.Further studies about the effects of composition and sequence distribution of copolymers on structure of the blend fibers were made;and it was discovered that void volume in the blend fibers largely depends on the interface area between two polymer phases,and pore size and number on the particle size and number of the dispersing phase.An appropriate structural model about the blend fibers has been described.
The fine structures, paracrystal, porous and phase structures of blend acrylic fibers have bencharacterized using techniques based on X-ray diffraction, gas adsorption, density, electron and opticalmicroscopy, mercury penetration method and IR spectroscopic analysis. The existence of a fibril-void structure, with voids and fibrils of the order of 102.to 103A diameter has been confirmed for thewet-spun blend fibers. It was found that the blend acrylic fiber in the present work is a kind of ma-trix-fibril fiber;phase separation takes place in it.Further studies about the effects of composition and sequence distribution of copolymers on structure of the blend fibers were made;and it was discovered that void volume in the blend fibers largely depends on the interface area between two polymer phases,and pore size and number on the particle size and number of the dispersing phase.An appropriate structural model about the blend fibers has been described.
1986, 4(4): 336-340
Abstract:
Several polyphenylquinoxalines (PPQ's) containing chloro-atom in the side chain have been syn-thesized and characterized by IR, TGA, ITGA and DTA. High quality, flekible, glass-cast films andvarnished wires have been obtained. The Tg's values and thermal stabilities of these polymers wereguater than those without any chloro-atom substitutent.
Several polyphenylquinoxalines (PPQ's) containing chloro-atom in the side chain have been syn-thesized and characterized by IR, TGA, ITGA and DTA. High quality, flekible, glass-cast films andvarnished wires have been obtained. The Tg's values and thermal stabilities of these polymers wereguater than those without any chloro-atom substitutent.
1986, 4(4): 341-345
Abstract:
Spherulites of different morphological features have been obtained by varying the cooling rateof polypropylene melts through the crystallization temperature range from 120℃ to 90℃. It wasfound that SALS is very sensitive to the changes of internal structure of the spherulites, and information about their morphological difference can be obtained according to the model theories and statisticaltheories of SALS.
Spherulites of different morphological features have been obtained by varying the cooling rateof polypropylene melts through the crystallization temperature range from 120℃ to 90℃. It wasfound that SALS is very sensitive to the changes of internal structure of the spherulites, and information about their morphological difference can be obtained according to the model theories and statisticaltheories of SALS.
1986, 4(4): 346-352
Abstract:
The polymerization of α-eleostearic acid (α-ESA) in the dipalmitoylphosphatidylcholine (DPPC)-α-ESA liposome was studied. The polymerization was carried out by UV irradiation and was kineticfirst order. The rate constant depends on the ratio of DPPC to α-ESA in the liposome. A transitionpoint of reaction rate could be observed in the course of the polymerization, and it appearedearlier with elevated temperature. Before the transition point, the higher the DPPC to α-ESAratio the higher was the reaction rate;while after the transition point,the higher the DPPC to α-ESA ratio the lower was the reaction rate.
The polymerization of α-eleostearic acid (α-ESA) in the dipalmitoylphosphatidylcholine (DPPC)-α-ESA liposome was studied. The polymerization was carried out by UV irradiation and was kineticfirst order. The rate constant depends on the ratio of DPPC to α-ESA in the liposome. A transitionpoint of reaction rate could be observed in the course of the polymerization, and it appearedearlier with elevated temperature. Before the transition point, the higher the DPPC to α-ESAratio the higher was the reaction rate;while after the transition point,the higher the DPPC to α-ESA ratio the lower was the reaction rate.
1986, 4(4): 353-358
Abstract:
Morphology of bisphenol A polysulfone-polyoxypropylene segmented copolymers was inves-tigated by means of differential scanning calorimetry and transmission electron microscopy. Theresults show that the molecular weights of the hard and soft segments have a pronounced effect onthe morphology of these segmented copolymers, which may changr from three-phase to single-phasestructure depending on the size and the relahve size of the segments. Heat treatment will enhancethe process of phase separation, increasing the domain size of the dispersed phase.Results obtained by study on the dynamic mechanical properties of these copolymers well support the existence of three-phase morphological structure.
Morphology of bisphenol A polysulfone-polyoxypropylene segmented copolymers was inves-tigated by means of differential scanning calorimetry and transmission electron microscopy. Theresults show that the molecular weights of the hard and soft segments have a pronounced effect onthe morphology of these segmented copolymers, which may changr from three-phase to single-phasestructure depending on the size and the relahve size of the segments. Heat treatment will enhancethe process of phase separation, increasing the domain size of the dispersed phase.Results obtained by study on the dynamic mechanical properties of these copolymers well support the existence of three-phase morphological structure.
1986, 4(4): 359-369
Abstract:
Cis-platinum complexes used as antitumor drugs were attached onto preformed polymers toreduce the toxicity. Either alternating copolymer of styrene and maleic anhydride (CPSMA) orpolyacrylic acid (PAA) is readily dissolved in alkaline solution. The cis-platinum complexes areeasily converted into water soluble species when treated by silver nitrate in water. The expectedproducts could be obtained when the two aqueous solutions were brought together. The productswere characterized by elementary analysis, IR and XPS.The polymer derivatives could exchange Jigands with nucleophilic groups in biological environment and also exhibit antineoplastic activity.
Cis-platinum complexes used as antitumor drugs were attached onto preformed polymers toreduce the toxicity. Either alternating copolymer of styrene and maleic anhydride (CPSMA) orpolyacrylic acid (PAA) is readily dissolved in alkaline solution. The cis-platinum complexes areeasily converted into water soluble species when treated by silver nitrate in water. The expectedproducts could be obtained when the two aqueous solutions were brought together. The productswere characterized by elementary analysis, IR and XPS.The polymer derivatives could exchange Jigands with nucleophilic groups in biological environment and also exhibit antineoplastic activity.
1986, 4(4): 370-376
Abstract:
A series of polyurethane based on liquid chloroprene-hydroxyethyl methacrylate copolymer(CP-co-HEMA)-polystyrene (PS) interpenetrating polymer networks (PU-PS IPN) were synthe-sized. Some physical properties were examined and density behavior was investigated. In 60% polyurethane (PU) system, the tensile strength and density increased greatly. Transmission electronmicrographs showed that the phase separation existed and the sizes of PS domains dispersed in PUphase were about 500-4,000 A. In comparison with correlative PU-PMMA IPN system,which has the higher compatibility,this system showed an extensive phase separation and clear boundaries.There was no phase inversion observed even for 60% PU system in which PS was still the dispersed phase and PU the continuous phase.This was due to the relatively faster rate of formation of PU than that of ST polymerization.
A series of polyurethane based on liquid chloroprene-hydroxyethyl methacrylate copolymer(CP-co-HEMA)-polystyrene (PS) interpenetrating polymer networks (PU-PS IPN) were synthe-sized. Some physical properties were examined and density behavior was investigated. In 60% polyurethane (PU) system, the tensile strength and density increased greatly. Transmission electronmicrographs showed that the phase separation existed and the sizes of PS domains dispersed in PUphase were about 500-4,000 A. In comparison with correlative PU-PMMA IPN system,which has the higher compatibility,this system showed an extensive phase separation and clear boundaries.There was no phase inversion observed even for 60% PU system in which PS was still the dispersed phase and PU the continuous phase.This was due to the relatively faster rate of formation of PU than that of ST polymerization.
1986, 4(4): 377-380
Abstract:
Active radicals formed during the sonolysis of PVK (polyvinyl carbazole) and PMMA (polymethylmethacrylate) have been studied with the combination of spin thepping technique and ESR spectroscopy-The results show that: 1. For PVK, radicals CA and--CH2--CH--are produced during the ultrasonic irradiation and only the later can be trapped by MNP. 2. For PMMA, radicals --C and --CH2 are generated by sonolysis and both can be trapped by ND.
Active radicals formed during the sonolysis of PVK (polyvinyl carbazole) and PMMA (polymethylmethacrylate) have been studied with the combination of spin thepping technique and ESR spectroscopy-The results show that: 1. For PVK, radicals CA and--CH2--CH--are produced during the ultrasonic irradiation and only the later can be trapped by MNP. 2. For PMMA, radicals --C and --CH2 are generated by sonolysis and both can be trapped by ND.
