Patents by Inventor Rudolf Stephan

Rudolf Stephan has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6367275
    Abstract: Method of cooling air in under-roof spaces of buildings, comprising the following steps: a) mixing water, cement, aluminium powder and a material selected from sand, gravel and the like, into a smooth mixture; b) spreading the smooth mixture over the roof to obtain a uniform layer of porous concrete; c) drying the layer; and d) soaking the layer with water.
    Type: Grant
    Filed: January 26, 1999
    Date of Patent: April 9, 2002
    Assignee: Luigi Riva
    Inventor: Rudolf Stephan
  • Patent number: 4788253
    Abstract: The invention relates to a thermoplastic molding material of an elastomeric polymer A, a shell B grafted to the polymer A, and a copolymer C as rigid matrix. The amount of polymer A is 1 to 25 percent by weight based on the weight of A+B+C. It has a glass transition temperature, Tg, of less than 0.degree. C. and an average particle size of 200 to 750 nanometers (d.sub.50 value of the integral mass distribution) and is composed of: 50 to 99.9 percent by weight of at least one alkylacrylate with 1 to 8 carbon atoms in the alkyl radical and 0.1 to 5 percent by weight of a polyfunctional monomer which has a crosslinking action. Grafting shell B represents 5 to 40 percent by weight based on A+B+C and is composed of at least one of the monomers of the group of(b.sub.1) vinylaromatic monomers, and(b.sub.2) the ethylenically unsaturated monomers.Grafting shell B is prepared in two stages with 30 to 70 percent by weight of the monomers b.sub.
    Type: Grant
    Filed: April 17, 1987
    Date of Patent: November 29, 1988
    Assignee: BASF Aktiengesellschaft
    Inventors: Juergen Hambrecht, Burghard Schmitt, Johann Swoboda, Georg Wassmuth, Claus Bernhard, Rudolf Stephan
  • Patent number: 4634734
    Abstract: The invention relates to a thermoplastic molding material of an elastomeric polymer A, a shell B grafted to the polymer A, and a copolymer C as rigid matrix. The amount of polymer A is 1 to 25 percent by weight based on the weight of A+B+C. It has a glass transition temperature, Tg, of less than 0.degree. C. and an average particle size of 200 to 750 nanometers (d.sub.50 value of the integral mass distribution) and is composed of: 50 to 99.9 percent by weight of at least one alkylacrylate with 1 to 8 carbon atoms in the alkyl radical and 0.1 to 5 percent by weight of a polyfunctional monomer which has a crosslinking action. Grafting shell B represents 5 to 40 percent by weight based on A+B+C and is composed of at least one of the monomers of the group of(b.sub.1) vinylaromatic monomers, and(b.sub.2) the ethylenically unsaturated monomers.Grafting shell B is prepared in two stages with 30 to 70 percent by weight of the monomers b.sub.
    Type: Grant
    Filed: February 15, 1984
    Date of Patent: January 6, 1987
    Assignee: BASF Aktiengesellschaft
    Inventors: Juergen Hambrecht, Burghard Schmitt, Johann Swoboda, Georg Wassmuth, Claus Bernhard, Rudolf Stephan
  • Patent number: 4468353
    Abstract: An improvement in the alkoxylation of a compound having a reactive methylene group by contacting said compound with an orthoformic acid trialkyl ester in the presence of a catalyst, the improvement residing in employing at least 1.6 moles of orthoformic acid ester per mole of compound having a reactive methylene group and carrying out the process in the presence of a catalyst of the group of aliphatic carboxylic acids, anhydrides of aliphatic carboxylic acids, aromatic sulphonic acids, alkali metal alcoholates and alkanolamines.
    Type: Grant
    Filed: September 30, 1982
    Date of Patent: August 28, 1984
    Assignee: Dynamit Nobel AG
    Inventors: Otto Ackermann, Dieter Bretzinger, Herbert Schneidewind, Rudolf Stephan
  • Patent number: 4442263
    Abstract: Thermoplastic molding materials contain a copolymer A and a graft copolymer B. The copolymer A is a hard component comprising one or more copolymers of styrene and/or .alpha.-methylstyrene with from 20 to 40% by weight of acrylonitrile.The graft copolymer B comprises one or more crosslinked acrylate polymer with a mean particle size of 0.5-0.8 .mu.m (d.sub.50 value of the cumulative mass distribution), a particle distribution, expressed by the ratio ##EQU1## in the range Q.gtoreq.0.6, and a glass transition temperature Tg below 0.degree. C. A mixture of styrene and acrylonitrile in a weight ratio from 88:12 to 65:35 is grafted onto this rubber.
    Type: Grant
    Filed: July 16, 1982
    Date of Patent: April 10, 1984
    Assignee: BASF Aktiengesellschaft
    Inventors: Franz Brandstetter, Juergen Hambrecht, Rudolf Stephan, Heinz-Juergen Overhoff, Josef Schwaab, Claus Bernhard, Johann Swoboda, Adolf Echte
  • Patent number: 4433102
    Abstract: A thermoplastic molding material contains 50-90% by weight of a hard component A comprising one or more copolymers of styrene and/or .alpha.-methylstyrene with acrylonitrile, and 50-10% by weight of a graft copolymer B comprising 40-80% by weight of a crosslinked acrylate polymer which has a mean particle size greater than 0.8 .mu.m (d.sub.50 value of the cumulative mass distribution) and onto which 20-60% by weight of a mixture of styrene and acrylonitrile in a weight ratio of from 88:12 to 65:35 is grafted.The novel molding material is used for the production of moldings.
    Type: Grant
    Filed: July 19, 1982
    Date of Patent: February 21, 1984
    Assignee: BASF Aktiengesellschaft
    Inventors: Franz Brandstetter, Juergen Hambrecht, Rudolf Stephan
  • Patent number: 4393164
    Abstract: Transparent, impact-resistant thermoplastic molding materials produced from a rigid methylmethacrylate polymer A, a rigid styrene-acrylonitrile polymer B and a flexible graft copolymer C, made from grafting an alkylmethacrylate and optionally styrene onto a rubber grafting base.
    Type: Grant
    Filed: March 26, 1982
    Date of Patent: July 12, 1983
    Assignee: BASF Aktiengesellschaft
    Inventors: Graham E. McKee, Franz Haaf, Juergen Hambrecht, Klaus Benker, Rudolf Stephan, Hans Breuer
  • Patent number: 4277418
    Abstract: An improvement in the alkoxylation of a compound having a reactive methylene group by contacting said compound with an orthoformic acid trialkyl ester in the presence of a catalyst, the improvement residing in employing at least 1.6 moles of orthoformic acid ester per mole of compound having a reactive methylene group and carrying out the process in the presence of a catalyst of the group of aliphatic carboxylic acids, anhydrides of aliphatic carboxylic acids, aromatic sulphonic acids, alkali metal alcoholates and alkanolamines.
    Type: Grant
    Filed: February 26, 1979
    Date of Patent: July 7, 1981
    Assignee: Dynamit Nobel Aktiengesellschaft
    Inventors: Otto Ackermann, Dieter Bretzinger, Herbert Schneidewind, Rudolf Stephan
  • Patent number: 4200702
    Abstract: Thermoplastic molding compositions based on rubber-modified styrene-acrylonitrile copolymers containing a halogenated styrene oligomer as the effective flame-proofing agent which is sufficiently heat-stable, does not interfere with processing on conventional machinery, does not corrode or cause coatings on such machinery, and has virtually no adverse effect on the impact strength of the polymers. The flameproofing agent as a rule has a degree of polymerization of from 3 to 200 and can be incorporated into the polymer by conventional methods; the polymer may or may not contain additional synergistic agents and processing auxiliaries, which are incorporated in the conventional manner and in the conventional amounts.
    Type: Grant
    Filed: June 5, 1978
    Date of Patent: April 29, 1980
    Assignee: BASF Aktiengesellschaft
    Inventors: Hermann Gausepohl, Herbert Naarmann, Klaus Penzien, Rudolf Stephan
  • Patent number: 4104328
    Abstract: Impact-resistant thermoplastic molding compositions having a hard component comprising a styrene/acrylonitrile copolymer and a soft component comprising a graft copolymer of styrene and acrylonitrile on a rubbery polymer containing butadiene. The rubbery polymer serving as base for the graft copolymer is produced by polymerization or the monomer of monomers forming said polymer in aqueous emulsion and in the presence of a small amount of an alkanol of from 1 to 4 carbon atoms. The compositions have improved color and color stability and may be processed by conventional methods to form shaped articles.
    Type: Grant
    Filed: January 5, 1976
    Date of Patent: August 1, 1978
    Assignee: BASF Aktiengesellschaft
    Inventors: Johann Swoboda, Rudolf Stephan, Gerhard Heinz
  • Patent number: 4080393
    Abstract: A method for rectifying chlorinated hydrocarbon to removed therefrom substances which discolor or tarnish metals by contacting the chlorinated hydrocarbon with a compound which is an alkanolamine, morpholine, an N C.sub.1-8 alkyl morpholine, hexamethyleneimine or a mixture thereof and thereafter water washing the so contacted chlorinated hydrocarbon.
    Type: Grant
    Filed: October 1, 1976
    Date of Patent: March 21, 1978
    Assignee: Dynamit Nobel Aktiengesellschaft
    Inventors: Kurt Deselaers, Rudolf Stephan
  • Patent number: 4069265
    Abstract: A stabilized 1,1,1-trichloroethane composition containing, as stabilizer therefor, a mixture consisting of a nitrile, 1,4-dioxane, and nitromethane.
    Type: Grant
    Filed: March 1, 1976
    Date of Patent: January 17, 1978
    Assignee: Dynamit Nobel Aktiengesellschaft
    Inventors: Hermann Richtzenhain, Rudolf Stephan
  • Patent number: 3959397
    Abstract: A stabilized 1,1,1-trichloroethane composition containing, as stabilizer therefor, a mixture consisting of a nitrile, 1,4-dioxane, and nitromethane.
    Type: Grant
    Filed: October 23, 1973
    Date of Patent: May 25, 1976
    Assignee: Dynamit Nobel Aktiengesellschaft
    Inventors: Hermann Richtzenhain, Rudolf Stephan