Summary: A novel, stabilizer‐free dispersion polymerization with alkyl esters as reaction media gives uniform alternating microspheres of maleic anhydride (MAn)/vinyl acetate (VAc) copolymer. The diameter of the copolymer microspheres could be precisely controlled from 80 to 750 nm by changing the monomer concentration or feed ratio. Moreover, this new type of copolymer microspheres with reactive anhydride groups on the surface has good solubility in common nontoxic solvents such as water and ethanol.SEM image of the powder surface of copolymer microspheres formed at [MAn] = [VAc] = 1.5 M.imageSEM image of the powder surface of copolymer microspheres formed at [MAn] = [VAc] = 1.5 M.
Triphenylene-containing 1-decynes with different alkyl chain lengths and their polymers are synthesized and the effects of the structural variables on their mesomorphic properties are investigated. The monomers [HCϵC(CH 2 ) 8 CO 2 C 18 H 6 (OC m H 2mþ1 ) 5 ; m ¼ 4-9] are prepared by consecutive etherization, coupling, and esterification reactions. The monomers form columnar phases at room temperature. The polymerizations of the monomers are effected by [Rh(nbd)Cl] 2 , producing soluble polymers in high yields (up to 84%). The structures and properties of the polymers are characterized and evaluated by IR, NMR, TGA, DSC, POM, and XRD analyses. All the polymers are thermally stable, losing little of their weights when heated to 300 8C. The isotropization temperature of the polymers increases initially with the length of alkyl chain but decreases on further extension. Although the polymers with shorter and longer alkyl chain lengths adopt a homogeneous hexagonal columnar structure, those with intermediate ones form mesophases with mixed structures.
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