DUGi

Fully biodegradable polylactic composites reinforced with bleached softwood fibers

http://dugi.udg.edu/item/http:@@@@hdl.handle.net@@2072@@284758

The increasing environmental awareness of the society has led to the development of materials with a lowerenvironmental impact. Polylactic acid (PLA) is a biodegradable polymer with higher mechanical properties than PP.The scientific literature shows some interest in PLA reinforced biocomposites, but the published mechanical propertiesof such materials are comparatively low. In fact, the generation of a good interface, when the reinforcement contentsare higher than 30%, is nowadays unsolved. The main objective of this study is to obtain PLA biocomposites with agood interface and with satisfactory improvements in their mechanical properties against reinforcement contents.Bleached pine fibers, used as reinforcement, were prepared and shred with 1/3 and 2/3 of diglyme, in order to avoid theformation of hydrogen bonds among the cellulose fibers. Then, composite materials were obtained through kineticmixing. The composites were injection molded to make standard specimens and were submitted to tensile tests. Theresults showed that the addition of diglyme favored the formation of hydrogen bonds between the reinforcement andthe PLA. Only the fibers treated with 2/3 diglyme followed a linear positive progression of its tensile strength whenincreasing reinforcement contents were added. Although suitable results were obtained, it seems that these composites

Editura Academiei Romane