Open AccessThermoplastic moulding of regenerated silk
Author(s) -
Chengchen Guo,
Chunmei Li,
Hiep V. Vu,
Philip C. Hanna,
Aron Lechtig,
Yimin Qiu,
Xuan Mu,
Shengjie Ling,
Ara Nazarian,
Samuel J. Lin,
David L. Kaplan
Publication year - 2019
Publication title -
nature materials
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 14.344
H-Index - 483
eISSN - 1476-4660
pISSN - 1476-1122
DOI - 10.1038/s41563-019-0560-8
Subject(s) - silk , materials science , biocompatibility , composite material , thermal stability , amorphous solid , thermoplastic , nanomaterials , composite number , spider silk , polymer , nanotechnology , chemical engineering , chemistry , organic chemistry , engineering , metallurgy
Early insights into the unique structure and properties of native silk suggested that β-sheet nanocrystallites in silk would degrade prior to melting when subjected to thermal processing. Since then, canonical approaches for fabricating silk-based materials typically involve solution-derived processing methods, which have inherent limitations with respect to silk protein solubility and stability in solution, and time and cost efficiency. Here we report a thermal processing method for the direct solid-state moulding of regenerated silk into bulk 'parts' or devices with tunable mechanical properties. At elevated temperature and pressure, regenerated amorphous silk nanomaterials with ultralow β-sheet content undergo thermal fusion via molecular rearrangement and self-assembly assisted by bound water to form a robust bulk material that retains biocompatibility, degradability and machinability. This technique reverses presumptions about the limitations of direct thermal processing of silk into a wide range of new material formats and composite materials with tailored properties and functionalities.