Consolidating Rotten/Pulverized Silk Fabrics through Spatially Adaptive 3D Strong/Tough Framework Mediated Structural Shaping of Fiber Bundles

Developing advanced technologies for consolidation and shaping of rotten/pulverized silk fabrics (RPSFs) is of vital historical and cultural values, but currently reported strategies are still far from satisfactory. In this regard, a novel PEI/PEGDE/IPP method was proposed in this work. Briefly, a spatially adaptive 3D cross-linked PEI/PEGDE framework was constructed around the silk fiber bundles of RPSF to enhance the structural integrity, strength, toughness, and elasticity of RPSF through successive soaking of RPSF in ethanol solution of branched poly(ethylenimine) (PEI) and acetone solution of poly(ethylene glycol) diglycidyl ether (PEGDE). Then, isopropyl palmitate (IPP) molecules were introduced into the PEI/PEGDE framework to improve the softness and ductility of RPSF. Through three systematic orthogonal experiments ( i.e. , stiffness, chromaticity variation, and mechanical properties), the optimal initial feeding composition of PEI and PEGDE were screened out and determined to be 2 wt% and 2 wt%, respectively. A series of composition and structural identification indicated that the consolidation/shaping mechanism of the PEI/PEGDE/IPP method fitted with our initial theoretical assumption. Besides, the PEI/PEGDE/IPP treatment induced ordered arrangement of RPSF along (210) crystal plane and, therefore, could enhance the anti-tearing capability of RPSF, which also positive influence on long-term preservation of RPSF. When being applied to true RPSF historical relics, the PEI/PEGDE/IPP method didn’t change its color and texture, and could improve the mechanical stability of RPSF to some extent. Thus, the reported PEI/PEGDE/IPP method is promising for preservation of RPSF historical relics in the future.