ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • ASTRONAUTICS (GENERAL)  (3)
  • crosslinked domains  (1)
  • emulsifier-free  (1)
  • emulsion copolymerization, divinylbenzene  (1)
  • 1
    facet.materialart.
    Unknown
    Preparation of large-particle-size monodisperse latexes in space (1986)
    In:  Other Sources
    Details
    Publication Date: 2019-06-28
    Description: Results are reported of latex sphere polymerization experiments performed on two flights of the Columbia and three flights of the Challenger. The trials were carried out because polymerization of the spheres in space avoids coagulation, nucleation of a new crop of particles, and excessive stirring requirements, and allows growth of spheres larger than 4 microns diam. The Monodisperse Latex Reactor (MLR) held four stirred 100 cc sealed stainless steel cylindrical containers. The mixtures were monitored for the conversion times, volume decreases as spheres formed and the mixture temperature. The spheres were grown from 0.19 micron seeds. Details of the flight preparation efforts are outlined. In flights which did not experience mechanical malfunctions spheres 3-30 microns diam were grown that had noticeably lower size variations than did the ground-based control particles. The 10 micron diam spheres grown on STS-6 were accepted as standard reference material by the NBS and became the first products made in space to be commercially sold on earth; the 30 micron spheres also became NBS standards. The experiments confirmed all projected benefits of producing the spheres in space, as well as provided the opportunity to grow more larger offsize spheres by finishing the growths on earth.
    Keywords: ASTRONAUTICS (GENERAL)
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 2
    facet.materialart.
    Unknown
    Production of Large-Particle-Size Monodisperse Latexes in Microgravity (1985)
    In:  CASI
    Details
    Publication Date: 2019-06-28
    Description: A latex is a suspension of very tiny (micrometer-size) plastic spheres in water, stabilized by emulsifiers. The growth of billions of these tiny plastic spheres to sizes larger than can be grown on Earth is attempted while keeping all of them exactly the same size and perfectly spherical. Thus far on several of the Monodisperse Latex Reactor (MLR) flights, the latex spheres have been returned to Earth with standard deviations of better than 1.4%. In microgravity the absence of buoyancy effects has allowed growth of the balls up to 30 micrometers in diameter thus far. The MLR has now flown 5 times on the Shuttle. The MLR has now produced the first commercial space product; that is the first commercial material ever manufactured in space and marketed on Earth. Once it is demonstrated that these large-size-monodisperse latexes can be routinely produced in quantity and quality, they can be marketed for many types of scientific applications. They can be used in biomedical research for such things as drug carriers and tracers in the body, human and animal blood flow studies, membrane and pore-sizing in the body, and medical diagnostic tests.
    Keywords: ASTRONAUTICS (GENERAL)
    Type: NASA, Washington Microgravity Sci. and Appl. Program Tasks; p 154-155
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 3
    facet.materialart.
    Unknown
    Preparation of large-particle-size monodisperse polystyrene latexes in microgravity (1982)
    In:  Other Sources
    Details
    Publication Date: 2019-07-27
    Description: Three large-particle-size monodisperse latexes (3.44, 4.08, and 4.98 micron diameter) were prepared in an automated four-reactor apparatus on the third orbital mission of the 'Columbia' begun on March 22. Comparison with ground-based controls showed that the 4.98 micron-size flight sample was the more uniform; the uniformity at the other two sizes was about the same. The rates of polymerization in microgravity and on earth were the same within experimental error, demonstrating that radical-initiated vinyl addition polymerizations are unaffected by the weightless environment.
    Keywords: ASTRONAUTICS (GENERAL)
    Type: IAF PAPER 82-153
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 4
    Electronic Resource
    Electronic Resource
    Emulsifier-free emulsion copolymerization of styrene and sodium styrene sulfonate (1992)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 30 (1992), S. 171-183 
    Details
    ISSN: 0887-624X
    Keywords: latex ; sulfonate functional groups ; poly(styrene-sodium styrene sulfonate) ; emulsion copolymerization ; emulsifier-free ; enhanced gel effect ; ion association ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of the emulsifier-free emulsion copolymerization of styrene and sodium styrene sulfonate have been examined over a range of comonomer compositions. The rate of polymerization was found to increase dramatically in the presence of small amounts of sodium styrene sulfonate. This increase is attributed to the increased number of particles formed when sodium styrene sulfonate was present and to a gel effect enhanced by ion association. At low concentrations of functional comonomer, where a monodisperse product was obtained, a homogeneous nucleation mechanism of particle generation is proposed. At higher concentrations, broader and then bimodal size distributions were obtained, and this is ascribed to significant aqueous phase polymerization of sodium styrene sulfonate. The water-soluble homopolymer is supposed to act as a locus of polymerization. The occurrence of this aqueous phase side reaction and the generation of secondary particles makes impossible the preparation of highly sulfonated polystyrene latexes by batch or seeded batch emulsion copolymerization.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1992.080300201
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Synthesis and characterization of monodisperse porous polymer particles (1992)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 30 (1992), S. 235-244 
    Details
    ISSN: 0887-624X
    Keywords: monodisperse particles ; emulsion copolymerization, divinylbenzene ; porous particles ; macroporous structure ; linear polymer, diluent ; crosslinked domains ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Monodisperse porous polymer particles in the size range of 10 μm in diameter were prepared via seeded emulsion polymerization. Linear polymer (polystyrene seed) or a mixture of linear polymer and solvent or nonsolvent were used as inert diluents. The pore diameters of these porous polymer particles were on the order of 1000 Å with pore volumes up to 0.9 mL/g and specific surface areas up to 200 m2/g. The physical features of the porous polymer particles depended on the diluent type and the crosslinker content, as well as the molecular weight of polymer seed particles. By varying the molecular weight of the linear polymer, monodisperse porous polymer particles with different pore size distribution could be synthesized. Polymer seed with a low degree of crosslinking instead of linear polymer could also be used to prepare monodisperse porous polymer particles with smaller pore volume and pore size.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1992.080300208
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...