abstract |
A method is provided to form a biodegradable aliphatic polyester suitable for use in fibers. In one embodiment, for example, an aliphatic polyester is melted and mixed with an alcohol to initiate an alcoholysis reaction resulting in a polyester having one or more hydroxyalkyl or alkyl terminal groups. By selectively controlling the conditions of alcoholysis (for example alcohol and polymer concentrations, catalysis, temperature, etc.), a modified aliphatic polyester having a molecular weight lower than the starting aliphatic polyester can be achieved. Such lower molecular weight polymers also have the combination of a higher melt flow rate and a lower apparent viscosity which is useful in a wide variety of fiber forming applications, such as in the meltblown of nonwovens. woven |