ARS | Publication request: BLENDS OF CYSTEINE-CONTAINING PROTEINS

Submitted to: APS Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: March 24, 2005
Publication Date: March 24, 2005
Citation: Barone, J.R., Schmidt, W.F. 2005. Blends of cysteine-containing proteins [abstract]. APS Annual Meeting. Paper No. V31.00014.

Interpretive Summary: Proteins can be obtained from agricultural wastes. For instance, keratin can be obtained from poultry feather waste, lactalbumin from whey, albumin from eggs, and gluten from wheat. All of these proteins contain cysteine, which makes them robust proteins. Suitable processing and blending avenues are described to turn these waste proteins into robust polymers that can be used to make films or molded plastic parts. This would be a huge advantage in making plastics from sustainable, i.e., non-petroleum, resources. In blending the proteins, synergies are found in the properties and the origin of the synergy is found through spectroscopic and thermal methods.

Technical Abstract: Many agricultural wastes are made of proteins such as keratin, lactalbumin, gluten, and albumin. These proteins contain the amino acid cysteine. Cysteine allows for the formation of inter- and intra-molecular sulfur-sulfur bonds. In addition, the agricultural proteins contain large amounts of 'OH containing amino acids serine, threonine, and tyrosine. Correlations are made between the properties of films made from the proteins and the amino acid sequence. Blends of cysteine-containing proteins show possible synergies in physical properties at intermediate concentrations. FT-IR spectroscopy shows increased hydrogen bonding at intermediate concentrations suggesting that this contributes to increased physical properties. DSC shows limited miscibility and the formation of new crystalline phases in the blends suggesting that this too contributes.