摘要:

AbstractPoly(methacrylic acid‐co‐methacrylamide) and poly(acrylic acid‐co‐acrylamide) have been synthesized and characterized by known methods. The respective comonomer units of the two copolymers enter into complex formation through hydrogen bonding and ion‐dipole interactions. The unreacted units in the intercopolymer complex also interact with homopolymers such as poly(N‐vinylpyrrolidone) and poly(oxyethylene) as well as transition metal ions to form three and four component intermacromolecular complexes. Formation of these complexes could be shown through several experimental techniques, e.g. viscometry, conductometry, potentiometry, IR and UV spectr

ISSN:0003-3146    

DOI:10.1002/apmc.1992.052000101

出版商:Hüthig&Wepf Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractSelected grades of low density polyethylene (LDPE) and linear low density polyethylene (LLDPE) were melt‐mixed and the physical, mechanical and rheological properties evaluated. The blends were found to combine the good mechanical properties of LLDPE and processing properties of LDPE. The effect of crosslinking the blends with dicumyl peroxide (1 phrParts per hundred rubber) was also investigated. The level of crosslinking increased with increase in LLDPE content. While the mechanical properties of the crosslinked blends were more uniform, the physical properties controlled by the crystallinity of the polymer, such as density, hardness and volume loss on abrasion, decreased on crosslinkin

ISSN:0003-3146    

DOI:10.1002/apmc.1992.052000102

出版商:Hüthig&Wepf Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractMacroporous copolymers of poly(acrylonitrile‐co‐divinylbenzene) were synthesized in the presence of 2‐ethyl‐1‐hexanol (2EH) and toluene as diluents. The copolymers were characterized by acrylonitrile content and from morphological point of view. Samples with a minimum content of homopolymer were transformed into weak base anion exchangers by the aminolysis‐hydrolysis reaction of the nitrile groups with N,N‐dialkylaminoalkylamines. The reactions were investigated by the exchange capacity variation and IR‐spectral analysis. It was emphasized that the reactivity of asymmetrical diamines depends on the nucleophilicity of the prim

ISSN:0003-3146    

DOI:10.1002/apmc.1992.052000103

出版商:Hüthig&Wepf Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractTetrafunctional initiators T4‐AZO4, T4‐TCE1 and T4‐IPDI4 have been synthesized by using insertion reaction of tetrakis(dimethylamino)‐titanium (T4) with 2,2′‐azoisobutyronitrile (AIBN), tetracyanoethylene (TCE) or isophorone diisocyanate (IPDI), respectively, in dry benzene under nitrogen at 35°C. T4‐AZO4 is useful for preparing four‐branch polymers from radically polymerizable monomers by decomposition of the azo groups incorporated in the related initiator. Four‐branch polyacrylonitrile can be synthesized by using the initiator T4‐TCE1. This initiator possesses titanium‐amino functionalities which are capable of initiating acrylonitrile polymerizations. The tetrafunctional isocyanate compound T4‐IPDI4 is found to be useful to prepare a model network of dihyd

ISSN:0003-3146    

DOI:10.1002/apmc.1992.052000104

出版商:Hüthig&Wepf Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractOxyethylene‐oxypropylene‐styrene multiblock copolymers were synthesized by coupling poly(ethylene glycol), poly(propylene glycol) and α, ω‐dihydroxy polystyrene with 2,4‐toluene diisocyanate. The purified copolymers were characterized by IR and1H NMR spectroscopy and membrane osmometry and identified as multiblock copolymers. The multiblock copolymers exhibit good emulsifying properties, high water absorption capacity and good phase transfer catalysis properties in Williamson reaction. The mechanical properties of the multiblock copolymers show that they behave like a thermoplastic elastomer or a toughened plastic, depending on the co

ISSN:0003-3146    

DOI:10.1002/apmc.1992.052000105

出版商:Hüthig&Wepf Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractDie photoinduzierte radikalische Vernetzung von Siliconacrylaten bzw. ‐methacrylaten wurde mit Hilfe von Quellungsmessungen untersucht, wobei ein modifizierter Quellungstest erlaubt, die Netzwerkbildung als Funktion verschiedener Parameter zu betrachten. Die Ergebnisse zeigen, daß die Netzwerkdichte eine Funktion der Lichtintensität, der Bestrahlungszeit, des Acrylatgehalts, der Molmasse des unvernetzten Silicons und auch der Länge der Spacergruppe zwischen Acrylateinheit und dem Siliconrückgrat ist. Sauerstoff besitzt dagegen nur einen Einfluß auf die Polymerisationskinetik, nicht aber auf die Netzwerkdichte.Aus dem Vergleich der δB, ‐Werte der vernetzten Siliconacrylate und der vernetzten Vinylsilicone kann geschlossen werden, daß die Netzwerkstruktur auch vom Typ der olefinischen Gruppen abhängt. Die χ‐Parameter besitzen jedoch im gleichen Konzentrationsbereich die gleiche Größe.Kinetische Untersuchungen zeigen, daß die Netzwerkbildung nach einem Zeitgesetz erster Ordnung verläuft. Dieses Ergebnis steht im Einklang mit der Polymerisationskinetik.Mit Hilfe der Quellexperimente ist es auch moglich, den Einfluß von H‐Siloxanzusätzen als Wasserstoffüb

ISSN:0003-3146    

DOI:10.1002/apmc.1992.052000106

出版商:Hüthig&Wepf Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractWood samples were treated with allylic ether resins having various molecular weights, various structures and with the use of different solvents. Using a technique based on Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR‐FTIR), differences in the characteristic bands of wood and resin were monitored throughout a piece of wood treated with resins and thus a penetration profile was demonstrated.ATR‐FTIR showed that there were differences in the chemical composition of the wood itself at different depths from the surface. The resins could be detected at a depth of more than 3 mm into the wood after 4 days of penetration by gravity. Using a characteristic band for wood as an internal standard, it could be demonstrated that penetration depends upon the solvent used, molecular weight of the resin and also morphology of the w

ISSN:0003-3146    

DOI:10.1002/apmc.1992.052000107

出版商:Hüthig&Wepf Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractA method of preparation of porous ion‐exchange membranes (PIEM's) with sulfonic groups is presented. One of the four studied polymer blends is recommended for PIEM's preparation. It is the ternary blend of polyethylene with poly(styrene‐co‐divinylbenzene), isotactic polypropylene, and calcium carbonate. The effect of blend composition on membrane properties is also discussed. Both blend components, PP and CaCO3, affected the membrane porosity while only PP governed the pore diameter. A model of PIEM's creation is suggested. The antifouling behaviour of PIEM's was evaluated by means of ultrafiltration of bovine serum albumine or poly(ethylene glycol) solutions as well as skimmed‐milk and an active sludge designated for bioconversion of aldehydes. It was found that membranes with ion‐exchange capacity higher than 1 mmol/g offer antifouling effect. PIEM's have also higher solute rejection parameter and are easier to regenerate than membranes without sulfon

ISSN:0003-3146    

DOI:10.1002/apmc.1992.052000108

出版商:Hüthig&Wepf Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractBlends aus isotaktischem Polypropylen (iPP) and trans‐Polyoctenylen (TOR) wurden mit Differentialkalorimetrie, Röntgenweit‐ und ‐kleinwinkelstreuung, Torsionsschwingungsanalyse und Polarisationsmikroskopie (Keimbildung und Kristallisationskinetik) untersucht. Schmelz‐ und Kristallisationstemperaturen ändern sich nur wenig als Funktion der Komponentenzusammensetzung; auch die Überstruktur ist nahezu invariant gegenüber der Konzentration des zugemischten TOR. Die aus den Verlustmodulmaxima der Torsionsschwingungskurven bestimmten Glastemperaturen zeigen jedoch interessante Abhängigkeiten. Durch Berechnung der Schiefe der G″‐(T)‐Maxima wird gezeigt, daß iPP‐Moleküle in die TOR‐Komponente diffundieren, in geringerem Maße auch TOR‐Moleküle in die iPP‐Matrix. Dadurch bildet sich ein Grenzschichtvolumen, in dem beide Komponenten lokal gemischt sind. Dieses Grenzschichtvolumen ist verantwortlich für den gemessenen erhöhten An

ISSN:0003-3146    

DOI:10.1002/apmc.1992.052000109

出版商:Hüthig&Wepf Verlag    

年代:1992

数据来源: WILEY

摘要:

AbstractBisphenol A novolacs were synthesized in a melting process using paraformaldehyde, and in a solution process using a formalin solution and oxalic acid catalyst.1H‐NMR investigations show a higher content of methylene bridges in the novolacs synthesized in a melting process. These novolacs were analysed by HPLC, GPC, DSC and FT‐IR spectroscopy. The molecular masses were determined by vapour pressure osmometry. The results were shown to be related with the molar ratio of the components. The bisphenol A novolacs were used as curing agents for epoxy resins. There exists a dependence of the gel times on the content of methylene bridges; this dependence is influenced by temperature. The activation energy for gel formation is nearly the same in all curing reactions investigated. The networks synthesized were investigated by thermomechanical analy

ISSN:0003-3146    

DOI:10.1002/apmc.1992.052000110

出版商:Hüthig&Wepf Verlag    

年代:1992

数据来源: WILEY