This article describes how to convert the unreactive surface of poly(tetrafluoroethylene) (PTFE) into poly(styrene-co-acrylonitrile) (SAN). Composite particles with a crosslinked poly(butadiene) (PB) shell covered over a PTFE core were prepared by an emulsifier-free seeded emulsion polymerization of butadiene in the presence of PTFE latex. It was found that the increase in the PB crosslink density resulted in depressing the formation of PB secondary particles. Then, styrene and acrylonitrile were able to graft onto PB shell in high efficiency of 70%. SAN-modified PTFE/PB coreshell particles could eventually be dispersed homogeneously in a SAN matrix.

The syntheses of two AB2 monomers, aminodicarboxylic acid (1) and aminodicarbonyl azide (2), and their model reactions for the one-pot synthesis of dendritic aromatic poly(urea-amide)s using the two AB2 monomers were carried out. The model reaction of 2 and p-tolyl isocyanate produced the target urea with two acyl azide groups in 93% yield at 25 °C for 30 min in tetrahydrofuran (THF). The Curtius rearrangement from an acyl azide to an isocyanate was completed at 140 °C for 30 min in THF. The isocyanate produced via the Curtius rearrangement readily reacted with aniline to give a urea compound in 93% yield. p-Tolyl isocyanate selectively reacted with an amine group of 1 to give a urea with end carboxylic acid groups. The end carboxylic acid groups of the urea could be activated with a condensing agent, diphenyl(2,3-dihydro-2-thioxo-3-benzoxazolyl)phosphonate (DBOP), and the condensation of the active amide with 2 provided an amide with acyl azide end groups.

Dendritic poly(amide-urea)s from the first to fourth generations with a very narrow molecular weight distribution were prepared from 1,1,1-tris(4-carboxymethyloxyphenyl)ethane as a core molecule, using aminodicarboxylic acid and aminodicarbonyl azide as two AB 2 monomers in a one-pot procedure. This procedure involves activation of end carboxyl groups with a condensing agent, diphenyl(2,3-dihydro-2-thioxo-3-benzoxazolyl)phosphonate, condensation of the active amide with aminodicarbonyl azide, the Curtius rearrangement in the presence of aminodicarboxylic acid, and, finally, capping of the end groups with p-tert-butylaniline. All dendritic polymers were obtained quantitatively and fully characterized by elemental analysis and IR and NMR spectroscopies. Number average molecular weights (M n) of dendritic poly(amide-urea)s were estimated by end group analysis, and each dendritic poly(amide-urea) had Mn close to the calculated value. Degrees of branching for the second and third generation dendritic polymers were found to be 0.93 and 0.90, respectively by 1 H NMR spectroscopy.

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