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Urethane block unit, structure

Polymer Syntheses. The block copolyether-urethane-ureas were synthesized from polypropylene glycol, methylene bis(4-phenylisocyanate), and ethylenediamine using a two-step solution polymerization (7). The repeat unit structure was ... [Pg.114]

The influence of block length on the spherulite growth rate can be found in a set of urethane linked poly(ethylene oxide) block copolymers.(75) The copolymers consisted of uniform block length of either 34,45 or 90 repeating units with total molecular weights that varied from several thousand to 3-6 x 10. The 34 repeating unit blocks (M = 1500) always crystallized in extended form. In contrast the 90 repeating unit blocks (M = 3900) crystallized in a folded structure at all... [Pg.261]

See other pages where Urethane block unit, structure is mentioned: [Pg.211]    [Pg.393]    [Pg.544]    [Pg.284]    [Pg.137]    [Pg.203]    [Pg.103]    [Pg.137]    [Pg.72]    [Pg.375]    [Pg.118]    [Pg.173]    [Pg.184]   
See also in sourсe #XX -- [ Pg.5 ]



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Block structures

Block structuring

Structural units

Structure units

Structure urethanes

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