The Technical Possibilities for a Regenerated Silk

The molecular properties of silk fibroin are such as to make the regeneration of silk worthy of serious consideration. Not only is the molecular weight such as to indicate at least 500 units in the polymer, but, also, the component residues are among the simplest amino acids, without bulky side groups. Thus, the interchain attraction is the highest of several representative polymers. The mechanical problems of silk regeneration are not easily overcome, however. Many solvents degrade the fibroin appreciably, and, so far as is known, aqueous solutions of concentration com parable to that found in the silkworm have not been made. The structural simplicity which gives rise to good polymer properties is also conducive to instability of aqueous solutions. While important in an over-all appraisal of silk regeneration, the economic problems are not discussed in this paper.