Sangeta Garg - Academia.edu (original) (raw)

Papers by Sangeta Garg

Research paper thumbnail of Studies on the properties and characteristics of starch–LDPE blend films using cross-linked, glycerol modified, cross-linked and glycerol modified starch

European Polymer Journal, 2007

Corn starch was modified by cross-linking with epichlorohydrin and plasticizer glycerol. X-ray di... more Corn starch was modified by cross-linking with epichlorohydrin and plasticizer glycerol. X-ray diffraction studies showed that relative crystallinity of the native and cross-linked starch were similar and were not affected by cross-linking. Different films were prepared by blending corn starch, cross-linked starch or glycerol modified starch in LDPE. The mechanical properties of the films were studied for tensile strength, elongation, melt flow index, and burst strength. The properties of the blend films were compared with LDPE films. It was observed that with the blending of 7.5% native starch, there was a decrease in tensile strength, elongation and melt flow index but burst strength increased. The tensile strength, elongation and melt flow index of the films containing cross-linked starch was considerably higher than those containing native starch but the burst strength showed a reverse trend. For native starch and cross-linked starch modified with glycerol, the elongation and melt flow index of the films increased but burst strength decreased. Surface scanning of the blend films were done by scanning electron microscope. Film containing cross-linked starch/glycerol modified starch in the blend was observed to be smoother than the native starch blend films.

Research paper thumbnail of Characterization and evaluation of acylated starch with different acyl groups and degrees of substitution

Carbohydrate Polymers, 2011

Corn starch was modified with acetyl, propionyl and butyryl groups at four different degrees of s... more Corn starch was modified with acetyl, propionyl and butyryl groups at four different degrees of substitution (DS). FTIR, X-RD, TG-DTA, SEM, swelling power, solubility, water binding capacity and light transmittance techniques were used to characterize the samples. Effect of DS and acyl groups on physicochemical properties of starch was studied. During acylation, the crystalline structure of starch got destroyed and starch surface was eroded. Acylated starch was thermally stable than native starch. Amylose content of the starch samples increased slightly after acylation. Swelling power and water binding capacity of native starch were 3.09 g/g and 89.8%, respectively. In acetylated, propionylated and butyrylated starch at low DS, these properties increased. But at high DS, these decreased to below that of native starch. Butyrylated starch at DS of 1.75 showed lower swelling power, and water binding capacity than acetylated starch at DS 2.55. Increase in DS and acyl group chain length from acetyl to butyryl group improved hydrophobic transformation of starch.

Research paper thumbnail of Characterization and evaluation of acylated starch with different acyl groups and degrees of substitution

Carbohydrate Polymers, 2011

Corn starch was modified with acetyl, propionyl and butyryl groups at four different degrees of s... more Corn starch was modified with acetyl, propionyl and butyryl groups at four different degrees of substitution (DS). FTIR, X-RD, TG-DTA, SEM, swelling power, solubility, water binding capacity and light transmittance techniques were used to characterize the samples. Effect of DS and acyl groups on physicochemical properties of starch was studied. During acylation, the crystalline structure of starch got destroyed and starch surface was eroded. Acylated starch was thermally stable than native starch. Amylose content of the starch samples increased slightly after acylation. Swelling power and water binding capacity of native starch were 3.09 g/g and 89.8%, respectively. In acetylated, propionylated and butyrylated starch at low DS, these properties increased. But at high DS, these decreased to below that of native starch. Butyrylated starch at DS of 1.75 showed lower swelling power, and water binding capacity than acetylated starch at DS 2.55. Increase in DS and acyl group chain length from acetyl to butyryl group improved hydrophobic transformation of starch.

Research paper thumbnail of Studies on the properties and characteristics of starch–LDPE blend films using cross-linked, glycerol modified, cross-linked and glycerol modified starch

European Polymer Journal, 2007

Corn starch was modified by cross-linking with epichlorohydrin and plasticizer glycerol. X-ray di... more Corn starch was modified by cross-linking with epichlorohydrin and plasticizer glycerol. X-ray diffraction studies showed that relative crystallinity of the native and cross-linked starch were similar and were not affected by cross-linking. Different films were prepared by blending corn starch, cross-linked starch or glycerol modified starch in LDPE. The mechanical properties of the films were studied for tensile strength, elongation, melt flow index, and burst strength. The properties of the blend films were compared with LDPE films. It was observed that with the blending of 7.5% native starch, there was a decrease in tensile strength, elongation and melt flow index but burst strength increased. The tensile strength, elongation and melt flow index of the films containing cross-linked starch was considerably higher than those containing native starch but the burst strength showed a reverse trend. For native starch and cross-linked starch modified with glycerol, the elongation and melt flow index of the films increased but burst strength decreased. Surface scanning of the blend films were done by scanning electron microscope. Film containing cross-linked starch/glycerol modified starch in the blend was observed to be smoother than the native starch blend films.

Research paper thumbnail of Studies on the properties and characteristics of starch–LDPE blend films using cross-linked, glycerol modified, cross-linked and glycerol modified starch

European Polymer Journal, 2007

Corn starch was modified by cross-linking with epichlorohydrin and plasticizer glycerol. X-ray di... more Corn starch was modified by cross-linking with epichlorohydrin and plasticizer glycerol. X-ray diffraction studies showed that relative crystallinity of the native and cross-linked starch were similar and were not affected by cross-linking. Different films were prepared by blending corn starch, cross-linked starch or glycerol modified starch in LDPE. The mechanical properties of the films were studied for tensile strength, elongation, melt flow index, and burst strength. The properties of the blend films were compared with LDPE films. It was observed that with the blending of 7.5% native starch, there was a decrease in tensile strength, elongation and melt flow index but burst strength increased. The tensile strength, elongation and melt flow index of the films containing cross-linked starch was considerably higher than those containing native starch but the burst strength showed a reverse trend. For native starch and cross-linked starch modified with glycerol, the elongation and melt flow index of the films increased but burst strength decreased. Surface scanning of the blend films were done by scanning electron microscope. Film containing cross-linked starch/glycerol modified starch in the blend was observed to be smoother than the native starch blend films.

Research paper thumbnail of Characterization and evaluation of acylated starch with different acyl groups and degrees of substitution

Carbohydrate Polymers, 2011

Corn starch was modified with acetyl, propionyl and butyryl groups at four different degrees of s... more Corn starch was modified with acetyl, propionyl and butyryl groups at four different degrees of substitution (DS). FTIR, X-RD, TG-DTA, SEM, swelling power, solubility, water binding capacity and light transmittance techniques were used to characterize the samples. Effect of DS and acyl groups on physicochemical properties of starch was studied. During acylation, the crystalline structure of starch got destroyed and starch surface was eroded. Acylated starch was thermally stable than native starch. Amylose content of the starch samples increased slightly after acylation. Swelling power and water binding capacity of native starch were 3.09 g/g and 89.8%, respectively. In acetylated, propionylated and butyrylated starch at low DS, these properties increased. But at high DS, these decreased to below that of native starch. Butyrylated starch at DS of 1.75 showed lower swelling power, and water binding capacity than acetylated starch at DS 2.55. Increase in DS and acyl group chain length from acetyl to butyryl group improved hydrophobic transformation of starch.

Research paper thumbnail of Characterization and evaluation of acylated starch with different acyl groups and degrees of substitution

Carbohydrate Polymers, 2011

Corn starch was modified with acetyl, propionyl and butyryl groups at four different degrees of s... more Corn starch was modified with acetyl, propionyl and butyryl groups at four different degrees of substitution (DS). FTIR, X-RD, TG-DTA, SEM, swelling power, solubility, water binding capacity and light transmittance techniques were used to characterize the samples. Effect of DS and acyl groups on physicochemical properties of starch was studied. During acylation, the crystalline structure of starch got destroyed and starch surface was eroded. Acylated starch was thermally stable than native starch. Amylose content of the starch samples increased slightly after acylation. Swelling power and water binding capacity of native starch were 3.09 g/g and 89.8%, respectively. In acetylated, propionylated and butyrylated starch at low DS, these properties increased. But at high DS, these decreased to below that of native starch. Butyrylated starch at DS of 1.75 showed lower swelling power, and water binding capacity than acetylated starch at DS 2.55. Increase in DS and acyl group chain length from acetyl to butyryl group improved hydrophobic transformation of starch.

Research paper thumbnail of Studies on the properties and characteristics of starch–LDPE blend films using cross-linked, glycerol modified, cross-linked and glycerol modified starch

European Polymer Journal, 2007

Corn starch was modified by cross-linking with epichlorohydrin and plasticizer glycerol. X-ray di... more Corn starch was modified by cross-linking with epichlorohydrin and plasticizer glycerol. X-ray diffraction studies showed that relative crystallinity of the native and cross-linked starch were similar and were not affected by cross-linking. Different films were prepared by blending corn starch, cross-linked starch or glycerol modified starch in LDPE. The mechanical properties of the films were studied for tensile strength, elongation, melt flow index, and burst strength. The properties of the blend films were compared with LDPE films. It was observed that with the blending of 7.5% native starch, there was a decrease in tensile strength, elongation and melt flow index but burst strength increased. The tensile strength, elongation and melt flow index of the films containing cross-linked starch was considerably higher than those containing native starch but the burst strength showed a reverse trend. For native starch and cross-linked starch modified with glycerol, the elongation and melt flow index of the films increased but burst strength decreased. Surface scanning of the blend films were done by scanning electron microscope. Film containing cross-linked starch/glycerol modified starch in the blend was observed to be smoother than the native starch blend films.