![]() From ethanolamine, diethanolamine to TEA, the numbers of hydroxyl groups, degree of nonlinearity and electric charge gradually increased. (29, 30) Addition of additives enhanced flexibility of the soy protein films. Soy protein films were too brittle to be tested and had low intrinsic viscosity, which was in accordance with several reports. Soy proteins with unfolded structure had higher intrinsic viscosity of solution, film flexibility and strength. ![]() To compare capability of different additives of unfolding soy protein, intrinsic viscosity of soy protein solution and tensile properties of soy protein films with various additives are shown in Table 1. (17) In addition, some chemical modifications could decrease the biodegradability of starch and increase the price, making modified starch unattractive as a slashing chemical compared to PVA. The price of starch is escalating recently as its demand increases much faster than production in food and biofuel industries. (15, 16) Unfortunately, the properties of starch-based sizes were not comparable to PVA on polyesters and their blends. (6) On the other hand, various types of chemically modified starch have been explored to replace PVA. However, these methods had fatal drawbacks, including long operation time and high costs, and therefore have not been used for real industrial applications. (10) Approaches, such as coagulation, (11, 12) adsorption, (13) and ultrafiltration (14) were also developed to reuse PVA. ![]() Most of the degradation studies focused on chemical and photochemical oxidation, (6-9) enzyme biodegradation, (3) and photocatalytic degradation. In addition, TEA-soy sizes had a BOD 5/COD ratio of 0.44, much higher than 0.03 for PVA, indicating that TEA-soy sizes were easily biodegradable in activated sludge.Ī considerable amount of studies on the degradation, reuse and substitution of PVA have been carried out. Industrial weaving results showed TEA-soy protein had relative weaving efficiency 3% and 10% higher than PVA and chemically modified starch sizes on polyester/cotton fabrics, and had relative weaving efficiency similar to PVA on polyester fabrics, although with 3– 6% lower add-on. Additives with multiple hydroxyl groups, nonlinear molecule, and electric charge could physically modify secondary structure of soy protein and lead to about 23.6% and 43.3% improvement in size adhesion and ability of hair coverage comparing to unmodified soy protein. However, soy protein sizes lacked film flexibility and adhesion for required high-speed weaving. Soy protein with good biodegradability showed potential as warp sizes in our previous studies. It has not been possible to effectively degrade, reuse or replace PVA sizes so far. Nonbiodegradable PVA sizes are widely used and mainly contribute to high chemical oxygen demand (COD) in textile effluents. Braiding is typically limited to tubular designs or shape formed tubular constructs and both woven and braided designs are susceptible to unravelling.Biodegradable sizing agents from triethanolamine (TEA) modified soy protein could substitute poly(vinyl alcohol)(PVA) sizes for high-speed weaving of polyester and polyester/cotton yarns to substantially decrease environmental pollution and impel sustainability of textile industry. However, as the fabric is unable to stretch, this limits the potential design options. Woven fabrics can be made flat, tubular and in a few other three-dimensional designs. Knitted textiles can be produced in a flat, tubular or as three-dimensional structures and in comparison to other textile manufacturing options they offer several advantagess. As a result the mechanical performance of the output fabric can be precisely managed. Knitted fabrics offer a significant design opportunity, because of the ability to customise, control and secure yarn placement. Knitted implantable textiles are popular as a component in medical devices across multiple therapy areas. Below, Aran Biomedical provide a simple overview of knitted textiles. When it comes to selecting a textile for your medical device, engineers can find the selection process quite daunting due to the vast array of implantable fabric designs available and the different performance attributes they offer. Lowest Profile Implantable Medical Textiles.ProTEX Med® Implantable Grade Polypropylene.
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