Home About us Contact | |||
Drawing Ratio (drawing + ratio)
Selected AbstractsMorphology and texture development of uniaxially stretched poly(ethylene naphthalene-2,6-dicarboxylate)JOURNAL OF APPLIED POLYMER SCIENCE, Issue 1 2007A. Douillard Abstract The texture development of PEN films with different semicrystalline morphologies have been studied by X-ray diffraction. These different structures have been obtained by uniaxially stretching PEN amorphous films at 100 and 160°C (below and above Tg) at different drawing ratios. Samples have also been characterized by DSC to determine the crystallinity ratios, the crystallization, and melting temperatures. To define the orientation of crystallites in the oriented samples, pole figures have been constructed, as a function of temperature and drawing ratio (DR) in the range 1.5,4. In the range from DR = 2 to 4 the orientation is clearly uniplanar-axial. At Tdraw = 100°C the crystallinity shown by DSC analysis is higher than the sample stretched at 160°C. The orientation is also higher when samples are stretched at 100°C. The naphthalene rings mainly stay in the plane of the film with a lower fraction perpendicular to the plane of the film. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 395,401, 2007 [source] The draw ratio,Deborah number diagram: A useful tool for coating applicationsPOLYMER ENGINEERING & SCIENCE, Issue 3 2006S. Bourrigaud The understanding of the basic physical effects of viscoelasticity on drawing performances in the coating process leads to a useful approach to link the rupture of the polymer melt to critical processing conditions. In particular, we show that when solving the drawing problem in the air gap with a simple constitutive equation,like the upper convected Maxwell model,a mathematical inconsistency appears for some drawing parameters. This mathematical instability may be experimentally correlated to the occurrence of melt-rupture, giving rise to a discussion on the effect of viscoelastic properties on drawing performances. Results are given in terms of a diagram representing the maximum drawing ratio Dr with respect to the Deborah number De. A master curve, obtained form experimental results, accounts for the temperature, melt-index, air-gap height, and extrusion output dependences. The limitations of the "universality" of the concept are discussed later. POLYM. ENG. SCI. 46:372,380, 2006. © 2006 Society of Plastics Engineers [source] Syndiotactic poly(propylene)/organoclay nanocomposite fibers: influence of the nano-filler and the compatibilizer on the fiber propertiesPOLYMERS FOR ADVANCED TECHNOLOGIES, Issue 5 2005Zita Mlynar, íková Abstract Melt spinning of nanocomposites prepared from syndiotactic poly(propylene) (sPP) and organolayered silicate (M-ODA), containing bound octadecyl ammonium chains, was investigated. The influence of the nano-filler reinforcement and the role of the addition of maleic anhydride grafted isotactic poly(propylene) (iPP-g-MA) as compatibilizer with respect to the fiber proportion was examined. The presence of nano-filler, the drawing ratio, and the compatibilizer addition afforded increased tenacity of the fibers. Only in the presence of the compatibilizer high drawing ratio of the sPP nanocomposite fibers was achieved. Transmission electron microscopy (TEM) was applied to monitor morphology development during nanocomposite fiber spinning in the presence and the absence of the compatibilizer. Copyright © 2005 John Wiley & Sons, Ltd. [source] Morphology and texture development of uniaxially stretched poly(ethylene naphthalene-2,6-dicarboxylate)JOURNAL OF APPLIED POLYMER SCIENCE, Issue 1 2007A. Douillard Abstract The texture development of PEN films with different semicrystalline morphologies have been studied by X-ray diffraction. These different structures have been obtained by uniaxially stretching PEN amorphous films at 100 and 160°C (below and above Tg) at different drawing ratios. Samples have also been characterized by DSC to determine the crystallinity ratios, the crystallization, and melting temperatures. To define the orientation of crystallites in the oriented samples, pole figures have been constructed, as a function of temperature and drawing ratio (DR) in the range 1.5,4. In the range from DR = 2 to 4 the orientation is clearly uniplanar-axial. At Tdraw = 100°C the crystallinity shown by DSC analysis is higher than the sample stretched at 160°C. The orientation is also higher when samples are stretched at 100°C. The naphthalene rings mainly stay in the plane of the film with a lower fraction perpendicular to the plane of the film. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 395,401, 2007 [source] |