Читать книгу Poly(lactic acid) - Группа авторов - Страница 69

Bis‐2‐oxazolines were described in the 1960s as useful in the preparation of poly(ester‐amide)s and manufacturing processes were later developed, for instance, for chain extension of aromatic polyesters [69, 70]. Bis‐2‐oxazolines have also been applied in the linking of LA‐based prepolymers. Prepolymers with predominantly carboxylic acid termination were linked using 2,2′‐bis(2‐oxazoline) as chain extender [71]. 2‐Oxazolines are inert toward aliphatic alcohols [72] and accordingly react selectively with the carboxyl end group of the prepolyester through ring‐opening between positions 1 and 5 of the oxazoline, yielding compounds possessing both amide and ester bonds (Figure 3.5).