Bibliographic Information

An XPS investigation of thermal degradation and charring processes for polymers in the condensed phase. I.     Wang, Jianqi; Tu, Hongbin; Jiang, Qinjun.    College of Chemical Engineering & Materials Science,  Beijing Institute of Technology,  Beijing,  Peop. Rep. China.    Journal of Fire Sciences  (1995),  13(4),  261-80.  CODEN: JFSCDV  ISSN: 0734-9041.  Journal  written in English.    CAN 123:315304    AN 1995:782658    CAPLUS   (Copyright 2004 ACS on SciFinder (R)) 

Abstract

Crosslinking and charring in the condensed phase of polymers during heating, processing, and/or burning are of central importance in their flame retardance and smoke suppression and in formulating polymeric composites.  Combining with thermal anal. techniques (TGA, DSC), ethylene-vinyl acetate (EVA) copolymers and polyethylenes (HDPE, LDPE) with/without inorg. phosphorus-contg. additives, were selected as model systems for XPS studies of the charring process.  A new parameter, Tgr, the transition temp. from mesophase to graphitic structure (graphite-like structure, GLS) of the char has been well-defined and detd. by combination of core levels and valence bands in XPS.  The reason for Tgr to be selected as a likely supplementary parameter for characterizing polymer charring in condensed phase is two-fold: (1) a clear-cut phase transition; (2) at which temp. a highly crosslinked network results.  A special emphasis was on roles of the oxygen atoms either introduced from an adventitious atm. or inherent Ac group itself.  Both thermal degrdn. and flame retardance of polymers were rationalized in terms of transition temp. Tgr.

Bibliographic Information

X-ray photoelectron spectroscopy (electron spectroscopy for chemical analysis) studies in flame retardancy of polymers.     Wang, Jianqi.    College Chemical Engineering Materials Science,  Beijing Institute Technology,  Beijing,  Peop. Rep. China.    ACS Symposium Series  (1995),  599(Fire and Polymers II),  518-35.  CODEN: ACSMC8  ISSN: 0097-6156.  Journal  written in English.    CAN 123:113809    AN 1995:734718    CAPLUS   (Copyright 2004 ACS on SciFinder (R)) 

 Abstract

 Thermal degrdn. of polymers and subsequent events (e.g. burning) occur rationally first from the surface exposed to the heat flux from surroundings and then go further in depth.  This article aims at introducing and exemplifying the potential applications of XPS, a surface sensitive tool, in flame retardancy of polymers, such as, thermal degrdn., structural identification, synergisms, and charring processes in the condensed phase.  Being coupled with other techniques C1s and O1s data about charring which can hardly be dealt with by conventional techniques were particularly provided and described.

Bibliographic Information

Studies of interface of polypropylene aluminum hydroxide composites by XPS.     Ren, Diansheng; Wang, Jianqi; Wu, Wenhui.    Tianjin Inst. Electron. Mater.,  Tianjin,  Peop. Rep. China.    Gaofenzi Cailiao Kexue Yu Gongcheng  (1993),  9(1),  101-4.  CODEN: GCKGEI  ISSN: 1000-7555.  Journal  written in Chinese.    CAN 121:232496    AN 1994:632496    CAPLUS   (Copyright 2004 ACS on SciFinder (R)) 

 Abstract

 Composites of Al(OH)3-filled polypropylene (PP) were studied.  The mech. properties were improved at high loading of Al(OH)3 in the system of Al(OH)3/KH-792 (silane coupling agent)/acrylic acid-grated polypropylene (AA-g-PP)/PP.  XPS was used to study the interfacial action of the composite.  All compns. of the Al(OH)3/KH-792/AA-g-PP/PP can react with each other, resulting in good mech. properties.

Bibliographic Information

 Synthesis and crystal structure of the complex [Lu(bzimpy-H)(NO3)2(CH3OH)2].bzimpy.2CH3OH.     Wang, Jianqi; Zhu, Ying; Wang, Shuangxi; Gao, Yici; Shi, Qizhen.    Department of Chemistry,  Lanzhou University,  Lanzhou,  Peop. Rep. China.    Polyhedron  (1994),  13(9),  1405-9.  CODEN: PLYHDE  ISSN: 0277-5387.  Journal  written in English.    CAN 121:168989    AN 1994:568989    CAPLUS   (Copyright 2004 ACS on SciFinder (R)) 

 Abstract

 The reaction of the ligand 2,6-bis(benzimidazol-2-yl)pyridine (bzimpy) with Lu(NO3)3.6H2O gave [Lu(bzimpy-H)(NO3)2(MeOH)2].bzimpy.2MeOH.  The Lu atom is 9 coordinate, and has 1 tridentate bzimpy-H anionic ligand, 2 bidentate NO3 groups, and 2 MeOH mols., bonded in a distorted tricapped trigonal prismatic geometry.

Bibliographic Information

 The potential applications of x-ray photoelectron spectroscopy (XPS) to the flame retardance mechanism of polymers.     Wang, Jianqi.    Coll. Chem. Eng. Mater. Sci.,  Beijing Inst. Technol.,  Beijing,  Peop. Rep. China.    Makromolekulare Chemie, Macromolecular Symposia  (1993),  74(4th Meeting on Fire Retardant Polymers, 1992),  101-10.  CODEN: MCMSES  ISSN: 0258-0322.  Journal  written in English.    CAN 121:158968    AN 1994:558968    CAPLUS   (Copyright 2004 ACS on SciFinder (R)) 

 Abstract

 XPS study of flame retardance of polymers is presented.  Degrdn. of polymers upon heating, synergisms, smoke suppression and structure were investigated.

Bibliographic Information

 Silicone oil as a flame retardant used in EPDM formulations.     Cui, Yan; Zeng, Minxiu; Huang, Youzhi; Wang, Jianqi.    Coll. Chem. Eng. Mater. Sci.,  Beijing Inst. Technol.,  Beijing,  Peop. Rep. China.  Editor(s): Ou, Yuxiang.    Proc. Beijing Int. Symp./Exhib. Flame Retard., 2nd  (1993),     138-44.  Publisher: Geol. Publ. House,  Beijing, Peop. Rep. China  CODEN: 59RJA2  Conference  written in English.    CAN 121:85476    AN 1994:485476    CAPLUS   (Copyright 2004 ACS on SciFinder (R)) 

 Abstract

 Flame retardancy of silicone oil used in EPDM and formulation of EPDM filled with ATH has been studied.  It is found that the interaction between silicone oil and the crosslinking agent is very complicated.  The mechanism of this flame retardant system is researched tentatively.  It is thought that silicone oil can participate the crosslinking reaction, promoting char formation as evidenced by the decrease of char forming temp.

Bibliographic Information

 The study of wool and wool treated with Zirpro treatment on heating by XPS.     Tu, Hongbin; Wang, Jianqi; Feng, Daming.    Coll. Chem. Eng. Mater. Sci.,  Beijing Inst. Technol.,  Beijing,  Peop. Rep. China.  Editor(s): Ou, Yuxiang.    Proc. Beijing Int. Symp./Exhib. Flame Retard., 2nd  (1993),     256-66.  Publisher: Geol. Publ. House,  Beijing, Peop. Rep. China  CODEN: 59RJA2  Conference  written in English.    CAN 121:59547    AN 1994:459547    CAPLUS   (Copyright 2004 ACS on SciFinder (R)) 

 Abstract

 In combination with TGA/DSC, XPS was used to study degrdn. and flame retardation of wool.  ZrOF2 is speculated to be of importance in flame retardancy and smoke suppression, the latter depending mainly on the contribution of covalent linkage in Zipro FR.

Bibliographic Information

 Flame retardance of red phosphorus and ammonium polyphosphate (APP) in polyethylene.     Jiang, Qinjun; Wang, Jianqi.    Coll. Chem. Eng. Mater. Sci.,  Beijing Inst. Technol.,  Beijing,  Peop. Rep. China.  Editor(s): Ou, Yuxiang.    Proc. Beijing Int. Symp./Exhib. Flame Retard., 2nd  (1993),     173-7.  Publisher: Geol. Publ. House,  Beijing, Peop. Rep. China  CODEN: 59RJA2  Conference  written in English.    CAN 121:58716    AN 1994:458716    CAPLUS   (Copyright 2004 ACS on SciFinder (R)) 

 Abstract

 The flame retardance performance of red phosphorus and ammonium polyphosphate in polyethylene and synergism between additives were discussed.

Bibliographic Information

 The study of thermal degradation of EVA copolymers by XPS/TGA/FTIR.     Wang, Jianqi; Tu, Hongbin.    Coll. Chem. Eng. Mater. Sci.,  Beijing Inst. Technol.,  Beijing,  Peop. Rep. China.  Editor(s): Ou, Yuxiang.    Proc. Beijing Int. Symp./Exhib. Flame Retard., 2nd  (1993),     272-9.  Publisher: Geol. Publ. House,  Beijing, Peop. Rep. China  CODEN: 59RJA2  Conference  written in English.    CAN 121:58552    AN 1994:458552    CAPLUS   (Copyright 2004 ACS on SciFinder (R)) 

 Abstract

 The thermal degrdn. of ethylene-vinyl acetate copolymers (EVA) with various VA% were studied by the XPS/TGA/FTIR combination which enables a variety of information to be derived, i.e. very useful results to the identification of degrdn. products in gas phase monitored by TGA/FTIR, the chem. structure of the residues surface can be simultaneously obtained from XPS anal.  As evidenced by x-ray photoelectron spectra of Cl atoms and valence band the increasing content of vinyl group in the EVA copolymer can cause Tmax of the first peak in DTG decreasing indicative of an earlier scission of the side chain, which would promote catalytically the char formation, confirmed by the appearance of graphite-like structure.

Bibliographic Information

 The effect of Al(OH)3/Mg (OH)2 on flame retardance of EVA copolymers.     Shen, Kang; Feng, Jin; Tu, Hongbin; Wang, Jianqi.    Coll. Chem. Eng. Mater. Sci.,  Beijing Inst. Technol.,  Beijing,  Peop. Rep. China.  Editor(s): Ou, Yuxiang.    Proc. Beijing Int. Symp./Exhib. Flame Retard., 2nd  (1993),     239-45.  Publisher: Geol. Publ. House,  Beijing, Peop. Rep. China  CODEN: 59RJA2  Conference  written in English.    CAN 121:36872    AN 1994:436872    CAPLUS   (Copyright 2004 ACS on SciFinder (R)) 

 Abstract

 Ethylene-vinyl acetate (EVA) copolymer is a polymer suitable for manufg. halogen-free, low-smoke, flame-retarded wire and cable materials.  This paper described the flame retarding effect of Al(OH)3/Mg(OH)2 on EVA copolymers (elastomeric Levapren 450 and Elavax 565)with different VA contents.  The influence of curing and blending with LDPE on flame retardance of EVA copolymer in the presence of Al (OH)3/Mg(OH)2 was also discussed.

Bibliographic Information

 Effect of structural factors on the rates of oxygen atom transfer to metal carbonyls.     Wang, Jianqi; Gao, Yici; Wang, Yaoyu; Shi, Qizhen.    Dep. Chem.,  Lanzhou Univ.,  Lanzhou,  Peop. Rep. China.    Wuji Huaxue Xuebao  (1994),  10(1),  35-9.  CODEN: WHUXEO  ISSN: 1001-4861.  Journal  written in Chinese.    CAN 120:332251    AN 1994:332251    CAPLUS   (Copyright 2004 ACS on SciFinder (R)) 

 Abstract

 The comparative study on kinetics and mechanism was made to examine further the importance of the CO bridging concept to the reactivity of metal clusters in the CO substitution by L of M4(CO)12-nLn(M = Co, Ir; L = phosphorous ligand; n = 1,2) in the presence of Me3NO.  The second-order rate law and kinetic behavior are the same as that reported earlier on such reaction and hence provide a common basis for comparison.  The reaction rates of Ir compds. are greater than those of corresponding Co compds. (Co < Ir) with the phosphorous ligands studied.  The results obtained here are different from earlier studies on the M3(CO)12 and M3(CO)11L (M = Fe, Ru, Os) where it was found that the reactivities decrease in the order Fe > Ru > Os and this is discussed in terms of the presumed important contribution of CO bridging to the rates of associative reactions in metal carbonyl clusters.  Some other effects of structural factors on rates of the oxygen atom transfer to metal carbonyls are also discussed.

上一頁(yè)  [1] [2] [3] [4] [5] [6] [7] [8]  下一頁(yè)