Stretching To Alter Polymer Properties By Elongation Patents (Class 528/502B)
  • Patent number: 6127501
    Abstract: Porous polyolefin membrane with a porosity of at least 20%, which is steam sterilizable at elevated temperature, wherein the polyolefin is polyethylene with an intrinsic viscosity of at least 5 dl/g and the membrane shows a shrinkage of at most 4% in every direction in the plane of the membrane when exposed to steam with a temperature of 134.degree. C. for 10 minutes.
    Type: Grant
    Filed: November 12, 1992
    Date of Patent: October 3, 2000
    Assignee: DSM N.V.
    Inventors: Henricus M. Fortuin, Petrus H. M. Stokman
  • Patent number: 5837806
    Abstract: A polyaniline is characterized by a nuclear magnetic resonance spectrum in its leuco form showing only two .sup.13 C peaks, indicating the substantal absence of chain branching, and preferably by a molecular weight (M.sub.p) above 90,000 and up to about 170,000 (more especially 100-140,000). Oriented films of such polyanilines in the protonated emeraldine oxidation state have electrical conductivities up to at least around 500 S/cm.They may be made by oxidizing aniline in aqueous solution with a persulfate under the combination of conditionsthat the acidity of the solution throughout the reaction is such that if its temperature is adjusted to 20.degree. C. it will have a pH in the range from about -0.2 to +3.0;that the temperature of the solution is in the range from -5.degree. to about -40.degree. C.
    Type: Grant
    Filed: February 22, 1996
    Date of Patent: November 17, 1998
    Assignee: BICC Public Limited Company
    Inventors: Phillip Norman Adams, Andrew Paul Monkman
  • Patent number: 5830554
    Abstract: An efficient method of producing a microporous polyolefin membrane having improved tensile strength and pierce strength is provided, in which a solution having dissolved therein 5% by weight to 50% by weight of a polyolefin whose weight-average molecular weight is in the range of 5.times.10.sup.5 to 2.5.times.10.sup.6 and whose weight-average molecular weight to number-average molecular weight ratio is less than 10, is extruded and rapidly cooled to obtain a gel-like product which is then stretched and has remaining solvent removed therefrom.
    Type: Grant
    Filed: September 24, 1996
    Date of Patent: November 3, 1998
    Assignee: Tonen Chemical Corporation
    Inventors: Norimitsu Kaimai, Kotaro Takita, Koichi Kono
  • Patent number: 5756660
    Abstract: A polyethylene article such as film or fiber having high strength and high elastic modulus is produced by orienting an ultra-high molecular weight polyethylene having an intrinsic viscosity at 135.degree. C. in decalin of 5 to 50 dl/g, said ultra-high molecular weight polyethylene being prepared by homo- or copolymerizing ethylene in the presence of a catalyst system and hydrogen, said catalyst system comprising (1) a solid catalyst component containing at least magnesium, titanium and/or vanadium, (2) an organometallic compound and (3) a compound represented by the following general formula ?I!: ##STR1## where R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are each hydrogen or a hydrocarbon residue, with the proviso that any two of R.sup.1, R.sup.2, R.sup.3 and R.sup.4 may conjointly form a cyclic hydrocarbon residue.
    Type: Grant
    Filed: October 2, 1996
    Date of Patent: May 26, 1998
    Assignee: Nippon Oil Company, Limited
    Inventors: Takeichi Shiraishi, Yoshiyuki Shimo, Seizo Kobayashi
  • Patent number: 5750645
    Abstract: A process which combines a calender with a stretching system and a set of heating rolls is provided in this invention to produce films of polypropylene resin of wide thickness range. The polypropylene films which have cavities distributed in the film and on the surfaces are suitable for writing or printing and have a low density. The films have surface qualities of each side of surface within .+-.2.times.10.sup.-6 inch of the average depth of the cavities, .+-.2% of the average of the gloss at 45.degree. angle and .+-.0.02 of the average of coefficient of friction. Such a film is obtained by passing the molded film from the calender through a set of heating rolls at temperatures revealed in this invention before entering the stretching system. The obtained polypropylene film has superior printability, low density and high stiffness, and thus is suitable for use as a paper substitute.
    Type: Grant
    Filed: May 10, 1996
    Date of Patent: May 12, 1998
    Assignee: Inteplast Corporation
    Inventor: Hwang-Wen Huang
  • Patent number: 5679758
    Abstract: Shaped articles are obtained from a polymerization mixture of soluble wholly aromatic polyamides in a gel state.
    Type: Grant
    Filed: March 30, 1995
    Date of Patent: October 21, 1997
    Assignee: Industrial Technology Research Institute
    Inventors: Jen-Chang Yang, Hung-Yi Hsiao, Jin-Chyueh Lin
  • Patent number: 5654394
    Abstract: A thermoplastic resin film wherein the variation in thickness of the film in the longitudinal direction is not more than 5% and the ratio "Pw1/PwT" of the sum of spectral intensities of wave-number components present in the wave-number range of 0.15 to 0.45 (1/m) (Pw1) to the sum of spectral intensities of the full wave-number range (PwT) determined when a wave form of the variation in thickness is subjected to analysis of Fourier transformation is not more than 0.20, and wherein the variation in thickness of the film in the longitudinal direction is not more than 5% and the ratio "Pw2/PwT" of the sum of spectral intensities of wave-number components present in the wave-number range of 1.00 to 2.00 (1/m) (Pw2) to the sum of spectral intensities of the full wave-number range (PwT) is not more than 0.15. In such a film, the uniformity in thickness can remarkably improved, and snaking and wrinkles in post processing can be prevented.
    Type: Grant
    Filed: April 4, 1995
    Date of Patent: August 5, 1997
    Assignee: Toray Industries, Inc.
    Inventors: Katsutoshi Miyakawa, Katsuya Toyoda, Akiko Yamamoto, Kenji Tsunashima, Toshiya Ieki
  • Patent number: 5652313
    Abstract: The present invention provides a two-stage melt process for the manufacture of thermoplastic, solvent-free, low-branched polycarbonates with low OH end-group contents with the use of ammonium or phophonium catalysts in the first stage and alkali and alkaline earth catalysts in the second stage.
    Type: Grant
    Filed: January 31, 1996
    Date of Patent: July 29, 1997
    Assignee: Bayer Aktiengesellschaft
    Inventors: Steffen Kuhling, Uwe Hucks, Gottfried Zaby, Claus Wulff
  • Patent number: 5474730
    Abstract: A thin, biaxially oriented polyester film which is asymetrically oriented by stretching 1-2 times in the machine direction and about 3-5 times in the transverse direction in the plane of the film is disclosed. The film has a birefringence of at least 0.085, an optical retardation of at least 9000 nanometers and a shrinkage of less than 2% in any direction at 150.degree. C. The film produced is substantially free of color fringes when viewed in partially polarized light. There are also disclosed two processes for the production of said film.
    Type: Grant
    Filed: June 9, 1993
    Date of Patent: December 12, 1995
    Assignee: Hoechst Celanese Corporation
    Inventors: Stephen J. Gust, Gregory W. Farell, Marshall D. Ledbetter
  • Patent number: 5439966
    Abstract: A temperature- and/or polar fluid-sensitive device which comprises a mechanically strained semi-crystalline hydrophilic polymer.
    Type: Grant
    Filed: January 7, 1993
    Date of Patent: August 8, 1995
    Assignee: National Research Development Corporation
    Inventors: Neil B. Graham, Marion E. McNeill
  • Patent number: 5431982
    Abstract: A unidirectionally long, biaxially oriented film of polyethylene-2,6-naphthalenedicarboxylate:(A) which has a Young's modulus of 400 to 600 kg/mm.sup.2 in the machine direction and a Young's modulus of at least 1,200 kg/mm.sup.2 in the transverse direction, the ratio of Young's modulus in the transverse direction to the Young's modulus in the machine direction being at least 2.5,(B) which has a heat shrinkage of 1% or less after heat-treated under no load at 105.degree. C. for 30 minutes, and(C) which has a surface roughness (Ra) of 0.005 to 0.010 .mu.m.This film is useful as a base film for magnetic tape having the capacity of log hours' recording and reproduction.
    Type: Grant
    Filed: July 19, 1994
    Date of Patent: July 11, 1995
    Assignee: Teijin Limited
    Inventors: Masanori Nishiyama, Yasuhiro Saeki