Corn Protein-Based Thermoplastic Resins:  Effect of Some Polar and Amphiphilic Plasticizers

Lodovico Di Gioia; Stéphane Guilbert

doi:10.1021/jf980976j

Mechanical and water barrier properties of corn-protein-based biodegradable plastics

Journal of Materials Research ◽

10.1557/jmr.2000.0375 ◽

2000 ◽

Vol 15 (12) ◽

pp. 2612-2619 ◽

Cited By ~ 12

Author(s):

Lodovico di Gioia ◽

Bernard Cuq ◽

Stéphane Guilbert

Keyword(s):

Relative Humidity ◽

Octanoic Acid ◽

Transmission Rate ◽

Barrier Properties ◽

Material Structure ◽

Water Barrier ◽

Corn Protein ◽

Water Glycerol ◽

Water Transmission ◽

Thermoplastic Resins

Experiments were performed to evaluate the mechanical and water barrier properties of corn-protein-based materials that were compression molded from thermoplastic resins. The influence of varying concentrations of water, glycerol, and octanoic acid was studied. At 0% relative humidity, the material exhibited a linear elastic deformation and a brittle fracture at any glycerol or octanoic acid content. Raising relative humidity from 0% to 97.3%, progressively decreased the tensile strength (from 24.1 to 2.2 MPa and 19.4 to 1.0 MPa), and the modulus of elasticity (from 1.67 to 0.03 GPa and 1.87 to 0.13 GPa), respectively, for the octanoic acid- or glycerol-plasticized materials. Increasing water content did not increase the tensile strain at break of the glycerol-plasticized material, whereas this parameter changed from 1.6 to 52.3% for octanoic-acid-plasticized material. This last material was waterproof during 21 h and its water transmission rate was then 0.05 mmolmm-2 s -1. Differences in water absorption were related to plasticizer solubility and material structure.

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172 Effects of Dietary Valine, Isoleucine, and Tryptophan Supplementations to Diets Containing Excess Leucine from Corn Protein on Growth Performance of Growing Pigs

Journal of Animal Science ◽

10.1093/jas/skab054.103 ◽

2021 ◽

Vol 99 (Supplement_1) ◽

pp. 61-62

Author(s):

Woongbi Bi Kwon ◽

Jose A Soto ◽

Hans H Stein

Keyword(s):

Block Design ◽

Control Diet ◽

Average Daily Gain ◽

Growing Pigs ◽

Experimental Unit ◽

Negative Effects ◽

Final Body Weight ◽

Corn Protein ◽

Dietary Treatments ◽

Daily Gain

Abstract An experiment was conducted to test the hypothesis that addition of Val, Ile, or Trp alone or in combination will reduce the negative effects of excess Leu in diets for growing pigs. A total of 288 growing pigs (28.6 ± 2.5 kg) were randomly assigned to 1 of 9 dietary treatments in a randomized complete block design. There were 2 barrows and 2 gilts in each pen and 8 replicate pens per treatment. A control diet based on corn and soybean meal and 8 diets based on corn and a high-protein corn product (48% crude protein) with 2 levels of crystalline L-Val (0 or 0.10%), L-Ile (0 or 0.10%), and L-Trp (0 or 0.05%) were formulated. The crystalline L-Val, L-Ile, and L-Trp increased standardized ileal digestible (SID) Val:Lys from 70 to 80%, SID Ile:Lys from 53 to 63%, and SID Trp:Lys from 18 to 23%, respectively. All diets were formulated to contain 1.00% SID Lys and the 8 diets containing corn protein contained 171% SID Leu:Lys. Individual pig weights were recorded at the beginning and at the conclusion of the 28-d experiment. Data were analyzed using the PROC MIXED of SAS with a pen as the experimental unit. Diet was the fixed effect and block and replicate within block were random effects. Results indicated that final body weight and average daily gain were not different between pigs fed the control diet and pigs fed the diet with Val and Trp addition, but greater (P < 0.001) than for pigs fed the diet with Val addition, Ile addition, Trp addition, Val and Ile addition, Ile and Trp addition, or Val, Ile, and Trp addition (Table 1). In conclusion, addition of Val and Trp to diets with excess Leu may prevent negative effects of excess Leu in diets for growing pigs.

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