摘要:

AbstractRadical homopolymerization and copolymerizations of a new ionic monomer, 3‐methyl‐2‐vinyl‐5,6‐dihydro‐4H‐1,3‐oxazinium trifluoromethanesulfonate (2c), were studied. The homopolymerization was initiated with 2,2′‐azoisobutyronitrile or benzoyl peroxide in acetonitrile to produce a polymer, poly[1‐(3‐methyl‐5,6‐dihydro‐4H‐1,3‐oxazinium‐2‐yl)ethylene] (3c), with a relatively low solution viscosity ([η] ≈ 0,2). The monomer was found to be copolymerizable with both electron‐rich (styrene and butyl vinyl ether) and electron‐deficient monomers [methyl methacrylate (MMA)]. For the copolymerization of the monomer and MMA the reactivity ratiosr1= 0,31 andr2= 0,37 (MMA) were determined. From these values theQandevalues were calculated to be 3,7 and 1,9, respectively. Thee‐value is one of the highest among vinyl monomers reported thus far, which is consistent

ISSN:0025-116X    

DOI:10.1002/macp.1986.021871201

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractSupports of polystyrene with long spacers were prepared by bromoalkylation of microporous, crosslinked polystyrene resins with ω‐bromoalkenes using CF3SO3H as catalyst. The dependence of the phase‐transfer catalytic activity of phosphonium salts bound to the polystyrene resins by long spacer chains, derived from the bromoalkylated polystyrene resins, on the percentage of ring substitution, on the degree of crosslinking, and on spacer‐chain length was studied. The high activity of the catalyst with long spacer chains was explained by the increased reactivity of the active site, induced by the increased lipophilicity of the catalyst, and by the facilitated ion exchange which was brought about by an increased distance between the active site and the polymer ba

ISSN:0025-116X    

DOI:10.1002/macp.1986.021871202

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractPolybutadienes of various microstructures and some butadiene copolymers were epoxidised to low levels (<1 mol‐%) withm‐chloroperbenzoic acid. The epoxide groups functioned as initiation sites for a “grafting‐from polymerization” of tetrahydrofuran (THF) catalysed by BF3. By conducting the reaction in dilute THF solution ([Monomeric unit]<0,3 mol · 1−1) with a large excess of BF3over epoxide groups, gel formation was avoided. The conversion of THF was less than 2% and the copolymers contained from 10 to 50% polytetrahydrofuran (PTHF) comprising graft chains of molar mass up to 43000 g · mol−1. The relative rate of grafting tended to decrease as the content of trans‐1,4 units in the backbone polymer increased, and, unusually, there was a small increase in volume during the graft copolymerization. The graft copolymers had a two‐phase morphology consisting of amorphous rubber and crystallites of PTHF. The latter function as physical crosslinks which break down above the melting point of PTHF, so that the materials behave as therm

ISSN:0025-116X    

DOI:10.1002/macp.1986.021871203

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractThe readily accessible 1,4:3,6‐dianhydroalditols with D‐gluco‐ (1), L‐ido‐ (5) and D‐mannoconfigurations (6) were efficiently transformed into the 2,5‐diamino‐1,4:3,6‐dianhydro‐2,5‐dideoxyalditols with D‐gluco‐ (10), D‐manno‐ (13), and L‐ido‐configuration (16). Interfacial polycondensation of these chiral heterocyclic diamines as well as ethylene‐ and tetramethylene diamine with the bis(chloroformate)3derived from 1,4:3,6‐dianhydro‐D‐sorbitol gave the polyurethanes17to21. Their number‐average molecular weights were determined to be M̄n≈ 3000 corresponding to an average degree of polymerisation P̄n≈ 20. Inherent viscosities were measured, and1H NMR spectroscopy as well as DSC gave informations about th

ISSN:0025-116X    

DOI:10.1002/macp.1986.021871204

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractIt could be demonstrated that methyl methacrylate (MMA) in a poly(methyl methacrylate) (PMMA)‐matrix can be polymerized by photoinduction with titaniumbiscyclopentadienyl dichloride (titanocene chloride). The photoinduced polymerized portion of MMA consists practically only of isotactic PMMA. The differences in polymerization by irradiation with laser light and with monochromatic light of a mercury light source with the same wavelength are discusse

ISSN:0025-116X    

DOI:10.1002/macp.1986.021871205

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY

摘要:

Abstract3‐Thienylacetylene (1) was prepared by reaction of 3‐(2,2‐dichloro‐1‐fluorovinyl)thiophene with butyllithium in a 1 : 2 mole ratio, and subsequent hydrolysis. Polymerization of1with WCl6and tetraphenyltin gave poly(1), poly[1‐(3‐thienyl)vinylene], which contained a small amount of benzene‐insoluble product. On heating poly(1) no weight loss was observed up to 240°C. At 500°C the weight loss was 18%. In differential scanning calorimetry, an exothermic peak appeared at 245°C. A pressed pellet, doped with iodine, exhibits conductivity of about 10−3S/cm. The absorption spectrum of poly(1) shows a shoulder at 225 nm, a maximum absorption at 360 nm and tailing up to about 660 nm. In a solution of poly(1) and I2, a new absorption appeared in the near‐infrared region, but failed to develop enough to suggest high conductivity of poly(1) doped with iodine. The electrochemical doping of poly(1) and electrochemical polymerization of1gave

ISSN:0025-116X    

DOI:10.1002/macp.1986.021871206

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractStudies of metathetic degradation of polybutadienes containing 70 to 80% of 2‐butene‐1,4‐diyl units (1) in presence of dimethyl 3‐hexenedioate (2) were carried out applying WCl6/Me4Sn as catalyst andr= [2]/[1] values varying between 0,4 and 0,01. The degradation was followed by steric exclusion chromatography, and the structural composition of degraded products was determined by1H NMR. Forr= 0,2, the degradation by cross metathesis between1and2, leading to α,ω‐bifunctionalized “prepolymers”, is superimposed by degradation via intramolecular metathesis and cationic cyclization of1units. Cationic side reactions (cyclization) are minimized by addition of ethyl acetate to the c

ISSN:0025-116X    

DOI:10.1002/macp.1986.021871207

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractPolymeric conjugates of adriamycin (ADR) (2) or daunomycin (DM) (3) were synthesized by reaction of the drugs with the copolymer of divinyl ether and maleic anyhdride (DIVEMA) (1). The content of ADR moieties in the DIVEMA conjugate (4) could be varied depending on the reaction conditions up to 35,8 wt.‐%. Considering the low toxicity and the high possibility of renal excretion, DIVEMA with M̄wof 7000 and M̄w/M̄n= 1,6 was used for the conjugation. The rate of drug release from the conjugate was determined under physiological conditions by reversed phase HPLC. Within 14 days only 15% of the attached ADR was released from conjugate4. The antitumor activity of the conjugates was tested in vitro and in vivo against mouse P388 leukemia. Conjugate4proved to be 28 times less active than ADR in vitro, which could be explained from the slow drug‐release. On the contrary 50% of the leukemic mice treated by4survived more than 60 days, whereas no mice given ADR alone or the admixture of ADR and DIVEMA survived 30 days. An antitumor activity of the polymeric conjugate better than that of the free drug was also observed in vivo with DM. Such a polymeric effect can be attributed either to the change in body distribution, the difference in pharmacokinetics, or the slow drugr

ISSN:0025-116X    

DOI:10.1002/macp.1986.021871208

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractSurface activeN‐oxyl radicals containing aliphatic chains were prepared from palmitinic, stearic and oleic acid chlorides by reaction with 4‐hydroxy‐(or‐4‐amino‐) 2,2,6,6‐tetramethyl‐piperidine or itsN‐oxyl. In the former case the resulting esters or amides were subsequently oxidized. A dioleyl ester (3b) was prepared analogously from 2,2,6,6‐tetramethyl‐4‐bis(2‐hydroxyethyl)aminopiperidine. Surface tension data of aqueous solutions were determined and micelle formation was confirmed by light transmission measurements. The size of the water droplets in hexane solution of the dioleoyl derivative was estimated by the fluorescence spectr

ISSN:0025-116X    

DOI:10.1002/macp.1986.021871209

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractThe anionic ring‐opening polymerization of ε‐caprolactone and 2,2‐dimethyltrimethylene carbonate in toluene as solvent with polystyryllithium or lithium polystyrylethoxide resp. lithium polystyrylmethoxide as initiators, results in the formation of the corresponding block polymers as major products, beside small amounts of homopolymer. The block copolymers were isolated chromatographically from the mixture and analyzed spectroscop

ISSN:0025-116X    

DOI:10.1002/macp.1986.021871210

出版商:Hüthig&Wepf Verlag    

年代:1986

数据来源: WILEY