Entretela hidrossolúvel à base de polímeros biodegradáveis

Abstract

The embroidery process in the textile industry requires the use of interlayer for a better finishing and firmament of the points. The objective of the present work was to develop a hydrosoluble interlayer based on cheap, available and biodegradable raw material. For this, films based on cassava starch and PVA (polyvinyl alcohol) were produced by the casting method, using glycerol as plasticizer and Sodium Lauryl Sulfate (LSS) as surfactant (foam stabilizer). The concentration of glycerol (15, 25 and 35% v/w to starch) and LSS (10, 15 and 20% v/w to starch) were determined according to Desing Factorial Complete 22, with three replicates in the center point. The films were characterized by subjective analysis (homogeneity, handling, adhesion, presence of bubbles and tearing propensity), thickness (digital micrometer); Humidity and Solubility in Water (by gravimetry); Infrared Spectroscopy with Fourier Transformed and Attenuated Total Reflectance (FT-IR-ATR) and Mechanical Properties (ASTM D882-02 (2002)). The thickness of the films ranged from 112 to 264nm. According to the mathematical model that best fitted the experimental data of tensile strength, when using glycerol (plasticizer) and LSS (surfactant) at lower levels, films are more resistant (18.6MPa) when compared to control (9.17MPa). In contrast, more flexible films were obtained with the use of higher plasticizer concentration and lower concentration of surfactant (80.60 and 121.99%) compared to the film without LSS (2.7%). The films containing LSS solubilized completely, it being impossible to quantify and terms of mean ± standard deviation the solubility of these in water. The statistical technique of desirability showed that the center point formulation (GLI: LSS - 25:15) is ideal for the production of more resistant, flexible films and with greater moisture retention capacity. The FT-IR-ATR of the films indicated a possible interaction between the terminals sulfonic of the LSS and the hydroxyls of the starch, assuming plasticizing action of the surfactant. The addition of Sodium Lauryl Sulfate (LSS) in starch-PVA-glycerol films may be favorable to obtain a water-soluble interlayer.