Results 211 to 220 of about 20,331 (261)

Cyclische monomere und oligomere in polyamid‐11 und polyamid‐12

Die Angewandte Makromolekulare Chemie, 1973
AbstractDer Gleichgewichtsgehalt an cyclischen Monomeren in hydrolytisch Polymerisiertem Polyamid‐11 und Polyamid‐12 bei 280°C wurde aus den Cyclisierungs‐konstanten nach STOLL und ROUVé sowie nach MORAWETZ und GOODMAN, der Gehalt an cyclischen Dimeren und Trimeren nach den statistisch abgeleiteten Beziehungen von JACOBSON und STOCKMAYER berechnet.Die ...
Von R. Feldmann, R. Feinauer
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Generalization of the static mechanical properties of plasticized polyamide-12 and polyamide-6

Polymer Science U.S.S.R., 1989
Abstract Generalization of the static mechanical properties of plasticized PA-12 andthe method of reduced variables over a wide temperature range has yielded a discrete series of values of the effective activation energy corresponding to the main relaxation processes. The character of change in effective activation energy with strain is regarded as a
J.V. Ivankina, I.G. Kuznetsova, V.V. Kovriga   +2 more
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New solvent for polyamides and its application to the electrospinning of polyamides 11 and 12

Polymer, 2007
Polyamides with long hydrocarbon chains, e.g. PA11 and PA12, are generally dissolved in phenolic or fluoric solvents that prevent these polymers from being electrospun and used in many applications because of their high boiling point and/or prohibitive cost. We demonstrate that a mixture of formic acid and dichloromethane can lead to the dissolution of
Kris Behler, Mickael Havel, Yury Gogotsi
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Relaxational properties of plasticized polyamide-12

Polymer Science U.S.S.R., 1979
The dielectric relaxation characteristics of polyamide-12 (polydodecalactam), plasticized by sulphonamides of the type RSO2NHC4H9 (where R is phenyl, β-naphthyl, 3-pyridyl or 8-quinolyl), were studied over a wide range of temperatures and frequencies (−100°C to + 100°C and 0.5–200 kHz). The glass temperature and relaxation time were determined, and the
A.I. Suvorova, T.P. Kashpurova, N.I. Novikov, A.A. Dukor, I.A. Nizova   +4 more
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Crystal structures and their effects on the properties of polyamide 12/clay and polyamide 6–polyamide 66/clay nanocomposites

Journal of Applied Polymer Science, 2006
AbstractBoth polyamide 12 (PA 12)/clay and polyamide 6–polyamide 66 copolymer (PA 6/6,6)/clay nanocomposites were prepared by melt intercalation. The incorporation of 4–5 wt % modified clay largely increased the strength, modulus, heat distortion temperature (HDT), and permeation resistance to methanol of the polyamides but decreased the notched impact
Y. Zhang, J. H. Yang, T. S. Ellis, J. Shi   +3 more
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Thermal Conductivity Measurements of Polyamide 12

2011
An important component in understanding the laser sintering process is knowledge of the thermal properties of the processed material. Thermal conductivity measurements of pure polyamide 12 were conducted based on transient plane source technology using a Hot Disk® TPS500 conductivity measurement device.
Yuan, Mengqi, Bourell, David, Diller, Tim   +2 more
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Effect of temperature on the fracture behavior of polyamide 12 and glass-filled polyamide 12 processed by selective laser sintering

Engineering Fracture Mechanics, 2018
Abstract The influence of the orientation and of the temperature on the mechanical properties of the polyamide 12 (PA12) and the polyamide 12 reinforced with glass beads processed via Selective Laser Sintering was analyzed. Tensile and fracture tests were performed at −50 °C, 23 °C and 50 °C with applied load perpendicular and parallel to the layered
A.J. Cano, A. Salazar, J. Rodríguez
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Investigation of structure development in polyamide 11 and polyamide 12 tubular film extrusion

Polymer Engineering & Science, 2002
AbstractThe processability of single bubble polyamide 11 and polyamide 12 films was investigated. The development of crystalline structure and chain orientation of polyamide 11 and polyamide 12 films in single bubble film blowing was studied by differential scanning calorimetry (DSC), wide angle X‐ray diffraction (WAXS), infrared (IR) spectroscopy, and
Sangkeun Rhee, James L. White
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One‐pot synthesis of polyamide 12,T–polyamide‐6 block copolymers

Journal of Polymer Science Part A: Polymer Chemistry, 2011
AbstractPolyamide 12,T–polyamide‐6 (PA‐12,T–PA‐6) block copolymers were synthesized by anionic polymerization of caprolactam using a PA‐12,T macrocoinitiator (McI). PA‐12,T McI and its precursors are soluble in molten caprolactam allowing for both the McI step‐growth polymerization and anionic polymerization to be performed in one‐pot.
Theodore F. Novitsky, Lon J. Mathias
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Colorometric study of polyamide-12 powder aging

Industrial laboratory. Diagnostics of materials, 2020
The key point of 3D printing by selective laser sintering is the necessity of complete filling of the working chamber of the printer with a powder material. Since the powder is not completely consumed during the printing process, 25 – 30 wt.% of secondary (unused in the previous cycle) power is added to the primary material in each cycle.
N. Ya. Mokshina, V. V. Khripushin, M. S. Shcherbakova   +2 more
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