posted on 2017-05-02, 14:19authored byHelan Xu, Kaili Song, Bingnan Mu, Yiqi Yang
A two-step technology
using nontoxic and eco-friendly chemicals
is developed for the durable setting of densely/highly crosslinked
proteins, such as wool and hair. Currently, most technologies for
morphological modification are effective only for materials from non-highly-crosslinked
proteins and cellulose. Before their morphological change, only water
is needed to interrupt hydrogen bonds and ionic linkages, which stabilize
the relative positions of molecules in non-highly-crosslinked proteins
and cellulose. However, highly crosslinked proteins contain disulfide
crosslinks, which are insusceptible to water. Thus, the controlled
cleavage of disulfide bonds is required for creating new morphologies
of highly crosslinked protein materials, such as hair and wool. Herein,
cysteine and citric acid (CA) were used for the two-step setting of
highly crosslinked proteins. This recipe showed better morphological
change and less mechanical loss than commercial hair styling products.
A reaction between CA and keratin was proposed, and verified via NMR
and Raman spectra and titration. This technology could be a prospective
alternative to achieve durable hair setting, anticrease finishing
of wool textiles, and other durable morphological changes needed for
highly crosslinked proteins.