Newly Developed Techniques on Polycondensation, Ring-Opening Polymerization and Polymer Modification: Focus on Poly(Lactic Acid).

Polycondensation and ring-opening polymerization are two important polymer synthesis methods. Poly(lactic acid), the most typical biodegradable polymer, has been researched extensively from 1900s. It is of significant importance to have an up-to-date review on the recent improvement in techniques for biodegradable polymers. This review takes poly(lactic acid) as the example to present newly developed polymer synthesis techniques on polycondensation and ring-opening polymerization reported in the recent decade (2005-2015) on the basis of industrial technique modifications and advanced laboratory research. Different polymerization methods, including various solvents, heating programs, reaction apparatus and catalyst systems, are summarized and compared with the current industrial production situation. Newly developed modification techniques for polymer properties improvement are also discussed based on the case of poly(lactic acid).

Cosmetic textiles with biological benefits: gelatin microcapsules containing vitamin C.

In recent years, textile materials with special applications in the cosmetic field have been developed. A new sector of cosmetic textiles is opened up and several cosmetic textile products are currently available in the market. Microencapsulation technology is an effective technique to control the release properties of active ingredients that prolong the functionality of cosmetic textiles. This study discusses the development of cosmetic textiles and addresses microencapsulation technology with respect to its historical background, significant advantages, microencapsulation methods and recent applications in the textile industry. Gelatin microcapsules containing vitamin C were prepared using emulsion hardening technique. Both the optical microscopy and scanning electron microscopy demonstrated that the newly developed microcapsules were in the form of core-shell spheres with relatively smooth surface. The particle size of microcapsules ranged from 5.0 to 44.1 microm with the average particle size being 24.6 microm. The gelatin microcapsules were proved to be non-cytotoxic based on the research findings of the toxicity studies conducted on human liver and breast cell lines as well as primary bone marrow culture obtained from patient with non-malignant haematological disorder. The gelatin microcapsules were successfully grafted into textile materials for the development of cosmetic textiles.