摘要:

AbstractAmorphous poly[(R,S)‐ß‐hydroxybutyrate], containing both phosphonoacetate and carboxylate functional end groups, was synthesized via anionic polymerization of racemic ß‐butyro‐lactone initiated by supramolecular complexes of potassiumP,P‐dimethylphosphonoacetate. The living homopolymers, with alkali metal counter ions complexed with a crown ether, were utilized for the synthesis of block copolymers via condensation reaction with alkylene dihalides. As a result of this approach, coupled block copolymers containing phosphonoacetate functional end groups we

ISSN:1022-1336    

DOI:10.1002/marc.1995.030160111

出版商:Hüthig&Wepf Verlag    

年代:1995

数据来源: WILEY

摘要:

AbstractThe polymerization of ε‐caprolactone (εCL) initiated with aluminium triisopropoxide (Al(OiPr)3) trimer (A3) and/or tetramer (A4) was studied. The rate ofA3⇔︁A4interconversions in the diluted (≤0,1 mol · L‐1) C6D6, C6D6/εCL, and THF/εCL solutions were found to be slow, when compared with the rate of propagation. Comparison of the1H NMR spectra of the initiators with those of the polymerization mixtures revealed thatA3is much more reactive thanA4in their reactions with εCL. From the initiator reacted with εCL all threeOiPr groups from Al(OiPr)3are transferred into the poly(εCL) as end groups. Kinetic studies of polymerization confirmed the large reactivity differ

ISSN:1022-1336    

DOI:10.1002/marc.1995.030160112

出版商:Hüthig&Wepf Verlag    

年代:1995

数据来源: WILEY

摘要:

AbstractSingle‐chain particles of poly(ethylene oxide) (PEO) were prepared by spreading a 10‐4wt.‐% solution of PEO in benzene on a hot water surface. After isothermal crystallization at 317,2 ± 0,1 K for 10 h, regular‐shaped single‐chain crystals were observed. A variety of typical morphologies were also found, and some of them are discussed on the basis of the habit of PEO crystals and various

ISSN:1022-1336    

DOI:10.1002/marc.1995.030160113

出版商:Hüthig&Wepf Verlag    

年代:1995

数据来源: WILEY

摘要:

AbstractThe isothermal crystallization behavior of thin films of isotactic poly(propylene) between plates coated with chromium, Teflon® or gold is studied by polarized light microscopy. At all contact surfaces between poly(propylene) and the other materials, transcrystallinity can be observed and competes with the growth of entities which originate in the bulk phase. The shape of these entities can be described by two intersecting paraboloids

ISSN:1022-1336    

DOI:10.1002/marc.1995.030160114

出版商:Hüthig&Wepf Verlag    

年代:1995

数据来源: WILEY

ISSN:1022-1336    

DOI:10.1002/marc.1995.030160115

出版商:Hüthig&Wepf Verlag    

年代:1995

数据来源: WILEY

ISSN:1022-1336    

DOI:10.1002/marc.1995.030160116

出版商:Hüthig&Wepf Verlag    

年代:1995

数据来源: WILEY