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) (Tm=257°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°C under atmospheric pressure and 60 min at 250-260°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 Tg and T m.
Посилання на статтю:
Segmented copolymers with poly(ester amide) units of uniform length: synthesis / R. J. Gaymans* and J. L. de Haan // Polymer. – 1993. – Vol 34. – P. 4360-4364.