SEGMENTED COPOLYMERS WITH POLY(ESTER AMIDE) UNITS OF UNIFORM LENGTH - SYNTHESIS

Segmented copolymers were synthesized from poly(tetramethylene oxide) with hydroxy end-groups or aliphatic diols and a short-chain diester diamide with a uniform length. The diester diamide (N,N'-bis(p-carbomethoxybenzoyl)butanediamine) (T(m) = 257-degrees-C) used is made from butanediamine and an excess of dimethyl terephthalate. The polymers are prepared in the melt with Ti(OCH3H7)4 as catalyst, for 30 min at 160-170-degrees-C under atmospheric pressure and 60 min at 250-260-degrees-C under a high vacuum. The polymers were studied by solution viscometry, differential scanning calorimetry and dynamic mechanical thermal analysis. The melting and glass transition temperatures decreased with increasing soft-block length. The crystalline order of the uniform unit is high and not very dependent on the soft-block length. The rate of crystallization is very fast. The moduli of these polymers are hardly dependent on temperature in the region between T(g) and T(m).