Viskositäts‐molmassen‐beziehung für poly(ethylenterephthalat‐co‐oxybenzoat)

Rafler, G.; Tesch, F.; Böhme, Frank

doi:10.1002/actp.1987.010381011

“…Two poly(ethylene terephthalate‐ co ‐oxybenzoate)s, LCP 1 and LCP 2 , were used for modification. Their inherent viscosities shown in Table I are nearly equal, and correspond to number‐average molecular weights of M n = 4060 and 4000 Dalton, respectively 34. From the content of carboxylic end groups and the assumption that the polyesters are carboxy terminated on both sides, M n of 4110 and 4650 Dalton were calculated for LCP 1 and 2 , respectively, which are in a good agreement with the M n determined by viscometry.…”

Section: Resultssupporting

confidence: 64%

Unsaturated 2-oxazoline end capping of liquid crystalline polyester by reactive processing and in a solution

Lustoň

¹

,

Böhme

²

,

Komber

³

et al. 1999

J. Appl. Polym. Sci.

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End capping of liquid crystalline poly(ethylene terephthalate-co-oxybenzoate) with a bifunctional 2-oxazoline derivative, 2-(4-allyloxyphenyl)-2-oxazoline, has been performed in melt under the condition of reactive processing and in a solution. The reaction in melt is very fast and, despite some modifier evaporation, it is completed in 2 min at 230°C. The product is a polyester containing unsaturated end groups bonded via esteramide linkage. The presence of unsaturation was proved by 13 C-NMR spectroscopy. An increase in temperature and prolongation of the processing time gives raise to thermal-induced reactions on the unsaturated end groups, resulting in an increase of the glass transition temperature. Depending on the processing temperature decomposition, propagation and crosslinking occur in different extent and influence polymer properties.

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“…Their inherent viscosities shown in Table 1 are nearly equal, and correspond to number-aver-age molecular weights of M n ϭ 4060 and 4000 Dalton, respectively. 34 From the content of carboxylic end groups and the assumption that the polyesters are carboxy terminated on both sides, M n of 4110 and 4650 Dalton were calculated for LCP 1 and 2, respectively, which are in a good agreement with the M n determined by viscometry.…”

Section: Resultssupporting

confidence: 56%

Unsaturated 2‐oxazoline end capping of liquid crystalline polyester by reactive processing and in a solution

Lustoň

¹

,

Böhme

²

,

Komber

³

et al. 1999

J. Appl. Polym. Sci.

Self Cite

View full text Add to dashboard Cite

End capping of liquid crystalline poly(ethylene terephthalate-co-oxybenzoate) with a bifunctional 2-oxazoline derivative, 2-(4-allyloxyphenyl)-2-oxazoline, has been performed in melt under the condition of reactive processing and in a solution. The reaction in melt is very fast and, despite some modifier evaporation, it is completed in 2 min at 230°C. The product is a polyester containing unsaturated end groups bonded via esteramide linkage. The presence of unsaturation was proved by 13 C-NMR spectroscopy. An increase in temperature and prolongation of the processing time gives raise to thermal-induced reactions on the unsaturated end groups, resulting in an increase of the glass transition temperature. Depending on the processing temperature decomposition, propagation and crosslinking occur in different extent and influence polymer properties.

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PET/PHB‐LC polyesters with improved mechanical properties — terminal group coupling with diisocyanate, I

Leistner

¹

,

Stephan²,

Häßler³

et al. 1993

Angew. Makromol. Chem.

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In order to increase the molecular weights of poly(ethy1ene terephthalate-co-oxybenzoate)s (PET/PHB) these polymers were modified with methylene-diphenyldiisocyanate (MDI) in the melt to couple the carboxy terminal groups, forming a copolyester amide. Starting from a, 12500, various R, values, partly up to 60 400, were obtained in dependence on the MDI quantity. The copolyester amides were characterized by IR spectroscopy, DSC, a, and rheological measurements. The MDI modification of PET/PHB causes also an increase in melt viscosity and a decrease in crystallinity in the solid state. Injection molded samples showed a considerable increase in tensile strength, elastic modulus and above all impact strength. ZUSAMMENFASSUNG:Zur Molmassenerhohung von Poly(ethylenterephtha1at-co-oxybenzoaten) (PET/PHB) wurden diese Polymeren in der Schmelze mit Methylendiphenyldiisocyanat (MDI) umgesetzt. Durch Kopplung der Carboxyendgruppen entstehen so Copolyesteramide, deren Molmasse von der zugesetzten MDI-Menge abhangt. Ausgehend von M, = 12500 konnten Molmassen bis zu 60400 erzielt werden. Die Copolyesteramide wurden mittels IR-Spektroskopie, DSC, Liisungsviskositats-und Schmelzviskositatsmessung charakterisiert. Die MDI-Modifizierung bewirkt eine Erhohung der Schmelzviskositat und das Absinken der Kristallinitat im Festkorper sowie einen signifikanten Anstieg der Zugfestigkeit, des E-Moduls und vor allem der Schlagzahigkeit (SpritzguDteile).-

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Viskositäts‐molmassen‐beziehung für poly(ethylenterephthalat‐co‐oxybenzoat)

Abstract: Acta Polymerica 38 (1987) Nr. (0 585ing that o w method gives the diffusion coefficients of the chains with the higher degree of polymerization, but from the inspection nf the conservation law of segment density it bccomes more ohvious [9].

Cited by 9 publications

References 5 publications

Unsaturated 2-oxazoline end capping of liquid crystalline polyester by reactive processing and in a solution

Unsaturated 2-oxazoline end capping of liquid crystalline polyester by reactive processing and in a solution

Unsaturated 2‐oxazoline end capping of liquid crystalline polyester by reactive processing and in a solution

PET/PHB‐LC polyesters with improved mechanical properties — terminal group coupling with diisocyanate, I

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