摘要:

AbstractZur Bestimmung des Modifikatorgehaltes von Stearinsäure(STS)‐bzw. Isopropyltriisostearyltitanat(Titanat)‐modifizierten CaCO3‐Füllstoffen wurde die simultane TG/DTA‐Analyse genutzt. die Methode wurde für Modellproben sowie für verschiedene kommerzielle Füllstoffe mit einem Konzentrationsbereich von 0 – 2,7% STS bzw. 0 – 4% Titanat angewendet. Eine ausreichende Übereinstimmung der Modifikatorkonzentrationen für STS, bestimmt durch simultane TG/DTA‐Analyse sowie eine C‐Analyse, wird erreicht, wenn der Zersetzungsbereich des Modifikators berücksichtigt wird. Dieser liegt für Stearinsäurezwischen180°C und 450°C (bei STS>1% bei 500°C) und für Isopropyltriisostearyltitanat zwischen 120 und 450°C (Titanat>1% bei 500°C) und wird aus dem Anstieg der TG‐bzw. DTA‐Kurve erhalten. Der diesem Zersetzungsbereich zuzuordnende Masseverlust entspricht bei STS‐modifizierten Füllstoffen dem Stearinsäuregehalt. Bei Titanat‐modifizierten CaCo3‐Füllstoffen ist ein Betrag von 10% des Masseverlustes hinzuzufügen. Für die Modifikatorgehaltsbestimmung von CaCo3‐Füllstoffen, die einen höheren Feuchtigkeitsgehalt (<0,2%) aufweisen, ist die Kenntnis dieser Größe notwendig, anderenfalls ist die ST

ISSN:0003-3146    

DOI:10.1002/apmc.1993.052050101

出版商:Hüthig&Wepf Verlag    

年代:1993

数据来源: WILEY

摘要:

AbstractInterpenetrierende Polymernetzwerke (IPN) wurden durch die gleichzeitige Vernetzung ungesättigter Polyesterharze und Dian‐Dicyanat erhalten. Die Copolymerisation von ungesättigtem Polyester mit Styrol erfolgte nach dem radikalischen Mechanismus, während das Dian‐Dicyanat cyclotrimerisierte, wodurch sich ein Polytriazin(Polycyanurant)‐ Netzwerk bildete. Die IPN zeichnen sich durch erhöhte Glastemperatur und mechanische Festigkeit im Vergleich zum entsprechenden ungesättigten Polyesterharz ohne Dian‐Dicyana

ISSN:0003-3146    

DOI:10.1002/apmc.1993.052050102

出版商:Hüthig&Wepf Verlag    

年代:1993

数据来源: WILEY

摘要:

AbstractA study was made of the removal of methyl orange (MO) solutes in water and in a pH 7 buffer solution by the reaction products of insoluble poly(glycidyl methacrylate) (PGMA) with tetraethylenepentamine (TEP) or polyethylenimine (PEI) having molecular weight of about 600 (PEI600). An examination was made of the adaptability of the Freundlich adsorption formula and the Klotz equation to removal behaviour of these polymers, which was noted to conform better to the Klotz equation than to the Freundlich adsorption formula. The removal rate and the amount removed were greater in water than in a pH 7 buffer solution, and decreased due to coexisting salts. The amount removed does not always depend on the amount of PEI600 groups bound to PGMA.

ISSN:0003-3146    

DOI:10.1002/apmc.1993.052050103

出版商:Hüthig&Wepf Verlag    

年代:1993

数据来源: WILEY

摘要:

AbstractThe paper describes the fabrication of cast acrylic sheets by copolymerizing a prepolymer syrup of methyl methacrylate (MMA) with varying amounts (1‐20 wt.‐%) of 2‐ethylhexyl methacrylate (EHMA), n‐hexyl methacrylate (HMA), 2‐ethylhexyl acrylate (EHA) and n‐hexyl acrylate (HA). The effect of structure of copolymer on light transmittance, density and mechanical properties was evaluated. Tensile strength and storage modulus decreased with increasing comonomer content. Strain increased significantly in the case of MMA/EHA and MMA/HA copolymer sheets having 15 and 20 wt.‐% of comonomer. Softening temperature of copolymer samples was determined using dynamic mechanical thermal analysis. Heat deflection temperature under flexural load and softening temperature decreased with increasing comonomer content

ISSN:0003-3146    

DOI:10.1002/apmc.1993.052050104

出版商:Hüthig&Wepf Verlag    

年代:1993

数据来源: WILEY

摘要:

AbstractStress‐strain behaviour of different blends of poly(ethylene‐co‐vinyl acetate) (EVA) (28 wt.‐% VA content) and low density polyethylene (LDPE) is studied under various strain rates and temperatures. It is found that stress‐strain plots of such semicrystalline polymer blends consist of three parts, namely, elastic or Hookeian region, region of chain slippage and region of strain hardening. Decrease in strain rate has an increasing effect on the strain hardening region. Increase in measurement temperature adversely affects the whole stress‐strain plot. It is apparent from the study that at an elevated temperature the process of strain hardening is dependent on the crystalline melting point of the major component in the blend. The X‐ray and DSC studies reveal that the process of strain hardening is mainly due to a change in internal order of crystallites in LDPE and LDPE‐rich blends, whereas in EVA and EVA‐rich blends it is due to induced crystallization in th

ISSN:0003-3146    

DOI:10.1002/apmc.1993.052050105

出版商:Hüthig&Wepf Verlag    

年代:1993

数据来源: WILEY

摘要:

AbstractPoly[(N‐(4‐hydroxyphenyl)maleimide)‐alt‐(p‐trimethylsilyl‐α‐methylstyrene)] (α‐PHTMMS) and several N‐(4‐hydroxyphenyl)maleimide ‐alt‐p‐α‐methylstyrene related copolymers were synthesized for novel positive near‐UV resists containing diazonaphthoquinone sulfonate (DNS). The chain‐stiffening effect of the maleimide group was responsible for high thermal resistance. Thus, a high glass transition temperature of 240°C and thermal decomposition temperature of 425°C were obtained. Lithographic positive images were obtained which resisted thermal deformation at 250°C. The prepared silicon‐containing resists were also used as the top imaging layer of a bilayer r

ISSN:0003-3146    

DOI:10.1002/apmc.1993.052050106

出版商:Hüthig&Wepf Verlag    

年代:1993

数据来源: WILEY

摘要:

AbstractThe polymerization of styrene in the presence of some fluorescent dyes, benzanthrone derivatives, has been investigated. The dependence of the polymerization rate of styrene on the character of the dye was determined. It was found spectrophotometrically that 70 – 80% of the dye reacted in the polymerization, thus the coloured fluorescent polymers were obtained. They are resistant to wet treatment and decolouration by solvent. The incorporation of the dye into the polymer chain does not significantly affect the molecular weight and polydispersity of the coloured polymer

ISSN:0003-3146    

DOI:10.1002/apmc.1993.052050107

出版商:Hüthig&Wepf Verlag    

年代:1993

数据来源: WILEY

摘要:

AbstractThis paper reports on a study of dynamic moduli and thermal transitions of poly(vinylidene fluoride) in compatible blends with poly(methylmethacrylate) and in non‐compatible blends with polystyrene. The effects of sepiolite on the compatibility of these blends have been studie

ISSN:0003-3146    

DOI:10.1002/apmc.1993.052050108

出版商:Hüthig&Wepf Verlag    

年代:1993

数据来源: WILEY

摘要:

AbstractRadiation‐vulcanization of natural rubber latex (NRL) with n‐butyl acrylate gives a higher tensile strength for films obtained after casting. The ageing properties of radiation‐vulcanized natural rubber in the presence of various antioxidants have been investigated. In order to find out suitable antioxidants for radiation‐vulcanized natural rubber latex (RVNRL) films, extraction of the gel fraction was carried out in xylene with 1 wt.‐% antioxidant and air bubbling. Antioxidants which give less reduction in gel fraction due to oxidative degradation during extraction are effective for ageing tests of RVNRL films. It was found that tris(nonylated phenyl) phosphite (Nonflex TNP) and 2,5‐di‐tert‐amylhydroquinone (Antage DAH), among 12 different antioxidants tested, were the most effective antioxidants

ISSN:0003-3146    

DOI:10.1002/apmc.1993.052050109

出版商:Hüthig&Wepf Verlag    

年代:1993

数据来源: WILEY

摘要:

AbstractPoly(sodium carboxylate)s containing varying amounts of unreacted sugar residues as biodegradable segments in the polymer backbone were prepared by the partial oxidation of amylose and cellulose using periodic acid/chlorite. It was found that dicarboxy polysaccharides containing sugar residues showed improved biodegradability comparing to those having no sugar blocks in the polymer chain, and their biodegradability varied according to the glucopyranose content or the degree of dicarboxylation. Dicarboxy polysaccharides containing more than 60% glucopyranose residues tended to biodegrade quickly. When compared on an equal glucopyranose content basis, the biodegradability of dicarboxy amylose(2b)was slightly superior to that of dicarboxy cellulose(2a). The builder performance in detergents was dependent on the degree of dicarboxylation, and a clear relation between the detergency and the content of carboxylate groups was observed. Dicarboxy polysaccharides with more than 40% dicarboxylation showed better builder performance than those of disodium 3‐oxapentanedioate and trisodium citrate, with some of them superior to that of sodium tripolyphosphate (STPP). The detergency of2bwas more effective than that of2a. It was also found that the detergency was improved much by increasing the amount of polymeric builde

ISSN:0003-3146    

DOI:10.1002/apmc.1993.052050110

出版商:Hüthig&Wepf Verlag    

年代:1993

数据来源: WILEY