Synthese und eigenschaften einiger höhergliedriger cyclischer ätheracetale

Optimized syntheses of 1,3,6,9-tetraoxacycloundecane ( 2 ), 1,3,6,9,12-pentaoxacylotetradecane ( 3 ), and 1,3,6,9,12,14,17,20-octaoxacyclodocosane ( 4 ) as well as some physical and chemical properties and the proof of structure are reported.     

Darstellung und eigenschaften von 2-(N-Aryl-N-methylamino)äthylmethacrylaten

A series of new 2-(N-aryl-N-methylamino)ethyl methacrylates ( 2a–f ) was synthesized. They may serve as polymerizable components in the initiation system diacyl peroxide/tertiary amme. Their physical properties, as density, refractive index, boiling point, NMR, and IR spectra, were determined. During the reaction with benzoyl peroxide the amines were transformed into gel-polymers. To determine the reactivity of these monomers towards peroxide, the rate constants of the reactions between benzoyl peroxide and the 2-(N-aryl-N-methylamino)ethanols 1a–f and between benzoyl peroxide and 2-(N-methyl-N-phenylamino)ethyl isobutyrate ( 3 ) were measured. Bulk polymerization of the unsaturated tertiary amines prepared was also corroborated.     

Synthese,thermostabilität und elektrische eigenschaften von tiefgefärbten polymeren mit anellierten phthalocyaninartigen systemen

2.5-Diamino-3.4-dicyanothiophene reacted with terephthalic aciddichloride to a polyamide and with thiophene-2.5-dicarboxaldehyde to a polyazomethine. A phthalocyanine analogous system could be built up on both polymers by the reaction with phthalodinitrile and copper acetylacetonate. This increased the thermal stability of the polymers. A new measurement cell was used to measure the electrical conductivity of the polymers. This cell is constructed to measure in any gas atmosphere or in a vacuum at pressures up to 5000 kp · cm^?2 and at temperatures up to 150°C.     

Polymerisation von fulvenen, 1. Synthese und eigenschaften kationischer polyfulvene

The cationic polymerization of a series of pentafulvenes with two exocyclic substituents yields highly reactive unsaturated polymers, which are soluble in nonpolar organic solvents. The preparative aspects as well as some properties of the polymers are discussed. Most polymers are very sensitive to oxygen. For instance poly(5-isopropylidene-3-cyclopenten-1,2-ylene) ( 2a ), which is obtained with molecular weights up to 350 000, consumes more than one mol-equivalent of oxygen per repeating unit.     

Synthese und thermische eigenschaften von photosensiblen polyacrylsystemen mit zimtsäurehaltigen seitengruppen und deren verwendung in composite-membranen

The synthesis of comb-like polymers containing cinnamic acid derivatives in the side chains is described. The disappearance of thermal transitions after UV-irradiation of the polymer samples was demonstrated by DSC measurements in the case of the liquid-crystalline homopolymer poly[4-propoxyphenyl 4-(6-acryloyloxyhexyloxy)cinnamate] and the side-chain crystallizable copolymers poly[(4-(6-acryloyloxyhexyloxy)cinnamic acid-co-hexadecyl acrylate)]. A significant influence of UV-irradiation on the permeation activation energy of 1-butanol through polyamide composite membrance containing a film of the photosensible comb-like polymers was observed.     

Darstellung und eigenschaften von poly-4-vinyltriarylmethylradikalen

As starting materials for the preparation of poly-4-vinyltriarylmethyl radicals the poly-4-vinyltriarylmethyl chlorides obtained from the corresponding carbinols were used. The conversion of the poly-4-vinyltriarylmethyl chlorides with zink powder leads to the corresponding carbon polyradicals only under complete exclusion of moisture. In the presence of traces of water poly-4-vinyltriarylmethyl cations are formed. The obtained poly-4-vinyltriarylmethyl radicals contain up to 100 radical electrons per macromolecule, as indicated by their e.s.r. spectra. In the presence of oxygen the carbon polyradicals form crosslinked polyperoxides; as intermediates unstable peroxiradicals can be identified by e.s.r. spectroscopy. With alkali metals the poly-4-vinyltriarylmethyl radicals form poly anions and, in case of polymers with biphenyl groups, polyradical anions.     

Lichtbeständige äthylencopolymere. Synthese und abbau durch lichteinwirkung

New photostable polyolefin systems containing controlled concentrations of covalently bound ultraviolet screening groups were prepared by copolymerization and rearrangement techniques. This chemical bonding approach, contrasted to the classical additive technique, avoids loss of ultraviolet absorber, permits relatively high concentrations of absorber to be used, and results in better weatherability. Polymers with bound o-hydroxybenzophenone units have the best ultraviolet stability of the absorbers studied. Ethylene/4-methacryloxy-2-hydroxybenzophenone copolymers were blended with high density polyethylene or isotactic polypropylene, permitting high concentrations of polymeric ultraviolet absorber to be retained in these polyolefins for the first time. Other ulraviolet absorbing comonomer units studied include allyl or acryloxy derivatives of o-hydroxyacetophenones, salicylates, 1-(o-hydroxyphenyl)-1,3-propanedione, and dibenzoylmethane.     

Herstellung und eigenschaften von photometrisch quantitativ bestimmbaren,bei der polymerisation vernetzenden bisacrylsäureestern und von bispropionsäureestern als modellverbindungen

Six bisacrylic acid esters containing structural groups which can be analyzed quantitatively by photometric methods were synthesized. The compounds were characterized by solubility data, spectra of IR and UV absorption and ¹H-NMR-spectra. Additionally bis propionic acid esters were synthesized; they are derived from bisacrylic acid esters through substitution of the acrylic acid units by propionic acid-units. Diluted solutions of bisacrylic and bispropionic acid esters obey BOUGUER -LAMBERT -BEER 's law within the range from 250 to 450 mμ. From the results of the homopolymerization of the bisacrylic acid esters it can be concluded which of the esters may be used for a simple photometric analysis of slightly crosslinked copolymers.     

Synthese von polyestern durch copolymerisation von dicarbonsäreanhydriden und ringäthern

Linear polyesters may be synthesized by copolymerization of dicarboxylic acid anhydrides and cyclic ethers according to anionic or cationic reaction mechanisms. Anionic copolymerization of dicarboxylic acid anhydrides and epoxides is catalyzed by salts of inorganic and organic acids, by alkalis, or amines. Reaction dependance from various experimental parameters was investigated. The polyesters are free from ether links and copolymerization runs strictly alternating. From experimental results a reaction mechanism for copolymerization of carboxylic acid anhydrides and epoxides was derived. Cationic copolymerization of dicarboxylic acid anhydrides with oxacyclic compounds such as five or higher membered cyclic ethers is catalyzed by complex cationic catalysts as LEWIS acid / cocatalyst or oxonium salts. The polyesters received partially contain ether links. Ether content varies with the molar ratio of monomers and especially with catalyst type and catalyst concentration. Polyesters partially containing ether or acetal links may also be prepared under the same conditions from polyethers or polyacetals and dicarboxylic acid anhydrides. Reaction mechanisms for the reactions investigated are suggested.     

Modifizierte ionenaustauscherharze — synthese und eigenschaften, 2. Synthese sulfoethylierter und sulfopropylierter styrol-divinylbenzol-harze

Sulfomethylated and sulfopropylated resins were prepared by polymer analogous reactions, starting from macroporous poly(styrene-co-divinylbenzene) matrices. Different reaction paths were used in the synthesis. It could be shown that sulfoalkylation can be achieved directly by reaction of the polystyrene resins with sultones. Alternatively, haloalkylated matrices were prepared and by halogen/sulfo-substitution the corresponding ion exchange resins.     

Synthese und Komplexierungseigenschaften von monomeren und polymeren 5-Methacryloylaminosalicylsäure-Derivaten

The synthesis of monomeric and polymeric 5-methacryloylaminosalicylic acid derivatives is described. The interaction of these ligands with Fe(III), Ti (IV) and Ca(II) ions was investigated by photometric, conductometric and viscosimetric measurements.     

Flexibilität und hydrodynamische eigenschaften von polymethylmethacrylat in binären mischlösungsmitteln

Light scattering and viscosity measurements of poly(methyl methacrylate) have been carried out, in order to investigate the correlation of unperturbed dimensions and intrinsic viscosity of the polymer relative to the thermodynamic properties of solvent mixtures as compared to results obtained in single component solvents. The unperturbed dimensions of the polymer turned out to be unaffected by the mixed solvent, whereas a strong dependence of the hydrodynamic radius on the enthalpy of mixing of the two solvent components was observed. Hence unequivocal conclusions about the chain structure of the dissolved polymer cannot be drawn from hydrodynamic measurements in mixed solvents. If values of the viscosity constant K₀ in these systems in the vicinity of the Θ-point are extrapolated according to the Burchard-Stockmayer-Fixman equation, they do not agree with data measured at T = Θ.     

Polychalkone. I. Synthese und eigenschaften thermostabiler polychalkone

The condensation polymerization (“polycrotonisation”) of aromatic dialdehydes with aromatic diacetyl compounds (CH₃CO? Ar? X? Ar? COCH₃) yielding polychalcones is discussed. The polymers obtained are thermally stable. The viscosity of only two polymers could be determined in dimethylformamide; the other polymers are insoluble in all solvents. As in the case of mono- and dichalcones, halochromy could be detected with the synthesized polychalcones. They exhibit paramagnetic properties and they are semi-conductors.     

Herstellung und eigenschaften von polyacenaphthylen, 3. Photoabbau von polyacenaphthylen

Thermally prepared polyacenaphthylene when irradiated in solution undergoes random chain scission. The photodegradation is solvent- and temperature-dependent and leads to a lower limit of the degree of polymerization. Polymeranalogous reactions and crosslinking can be found to occur simultaneously. A certain fraction of „weak links”︁ was detected in the polymer.     

Polymere mit phosphor-stickstoff-bindungen, 2. Synthese und eigenschaften von oligomeren mit Si?NP-struktureinheiten

Properties and syntheses of heteroorganic oligomers ( 3a–e ) from silylazides and ditertiary phosphines ( 2b–e ), or tetraphenylbiphosphine ( 2a ), respectively, are reported. One of the products ( 3a ) has a complete inorganic skeleton of the atomic sequence SiNPPN. Molecular weight measurements of oligomers synthetized in solution give values of M?_n near 1000, those of substances prepared in bulk give rise to values up to 4 300 depending on the phosphine used. The reaction can be followed by IR-spectroscopic measurements: v(P?N) of the synthesized compounds is tabulated. ³¹P-NMR measurements are of particular importance, because they permit statements about end and middle groups, i.e. about the structure of the products.     

Mechanismus der NCA-Polymerisation, 4. Synthese und Reaktionen von N-Acyl-NCA

Various N-acyl NCAs ( 8a–c, 14, 15 ) were prepared by reaction of N-acyl-N-trimethylsilylglycine trimethylsilyl esters ( 7a–c ) with phosgen or by addition of NCAs or of N-thiocarboxylic acid anhydrides (NTAs) on chlorosulfonyl isocyanate. Furthermore, the direct acylation of 4,4-dimethylglycine NCA and of several NTAs could be achieved with 3,5-dinitrobenzoyl chloride and triethylamine, a reaction, that involves NCA-anions 3 as intermediates, in analogy with the sulfenylation and silylation of NCAs 1 . N-Acyl NCAs (3-acyloxazolidine-2,5-diones) react with nucleophils exclusively at the carbonyl group C-5. The addition of N-acyl NCAs to a NCA-polymerization initiated by a tertiary amine enhances the rate of the polymerization, but lowers the polymerization degree, because any N-acyl NCA starts a growing chain by reaction with the NCA-anions 3 . The NCA-polymerization with high ratios of N-acyl NCA/NCA (1:4) yields, therefore, oligopeptides 20 , which show an acyl and an NCA endgroup in the IR- and the ¹H NMR spectrum. If the NCA-polymerization initiated by a tertiary amine is carried out in the presence of isocyanates, polypeptides with an urea and an NCA endgroup are obtained ( 25 ). These results prove, that the so called “activated monomer mechanism” is predominating in the case of the polymerization of N-unsubstituted NCAs 1 initiated by a tertiary amine. Pyridine as a weak base gives in high concentrations the same results as the strong base triethylamine. No evidence is found for a “zwitterionic mechanism” as with N-alkyl NCAs 2 described in Part 3 of this series. For the polymerization of four different NCAs 1 initiated with pyridine the relationships between reduced viscosity (η_sp/c) and conversion were established. These curves show for a 0 to 95% conversion a kinetic behaviour similar to a “living polymerization”; but from 95 to 100% conversion the viscosity increases exponentially due to condensation steps. The concentration of NCA end groups decreases by condensation and termination reactions even after 100% conversion of the monomers 1 . Various initiation, propagation, and termination reactions are discussed.     

Über polymere acide kohlenwasserstoffe. Synthese und eigenschaften von polymeren des 9-[2-vinylfluorenylidenmethyl]-fluorens

9-[2-Vinylfluorenylidenemethyl]-fluorene was prepared from 2-Vinylfluorene and 9-Bromomethylene-fluorene. The compound could be polymerized by means of radical as well as cationic initiators. A cross linked copolymer was obtained by copolymerization of the monomer with styrene and divinylbenzene. The polymers were converted to intensively red violett coloured polymer carbanions which could be discharged to polymer radicals by oxidizing agents.     

Das 13C-NMR-spektrum von alternierenden copolymeren aus äthylen und propylen

Alternating copolymers from ethylene and propylene were prepared by hydrogenation of cis-1,4-polyisoprene and isotactic trans-1,4-poly(1,3-pentadiene). In their ¹³C-NMR spectra meso and racemic diads were identified and assigned. The chemical shift of the meso diad appears to higher field.     

Polymere Protonenschwämme, 1. Synthese von Monomeren auf der Basis von Naphthalin und Fluoren

1,8-Bis(dimethylamino)-4-(4-vinylphenyl)naphthalene ( 33 ), 1,8-bis(dimethylamino)-4-(4-vinylbenzyl)napthalene ( 35 ), 4,5-bis(dimethylamino)-9-(4-vinylbenzyl)fluorene ( 37 ) and 4,5-bis(dimethylamino)-9,9-bis(4-vinylbenzyl)-fluorene ( 38 ) were synthesized as potential vinyl monomers.