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Kwang-mahn Kim - One of the best experts on this subject based on the ideXlab platform.
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mechanism study on surface activation of surfactant modified Polyvinyl Siloxane impression materials
Journal of Applied Polymer Science, 2004Co-Authors: Doug-youn Lee, Kwang-mahn Kim, Kyung Ho Chung, Kyoung-nam KimAbstract:This study examined the mechanism on the surface activation of hydrophilic Polyvinyl Siloxane impression materials incorporated with nonionic surfactants. Hydrophilic Polyvinyl Siloxane impression materials were prepared with a polydimethylSiloxane composition and nonionic surfactants. The surfactants used were nonylphenoxy poly(ethyleneoxy) ethanol homologs of varying ethyleneoxy chain length. These homologs were designated NP4, NP6, and NP10 according to the mole number of ethyleneoxy group (hydrophilic group) of 4, 6, and 10, respectively. The incorporation of a nonionic surfactant into Polyvinyl Siloxanes enhanced their hydrophilicity and consequently led to the significant reduction in the contact angles. The higher the concentration of surfactant that was incorporated, the lower the contact angles that were observed. The contact angle was lowest when NP4 was incorporated, even though NP4 is less hydrophilic than NP6 and NP10, which implies that the exposed surfactant concentration on the surface was highest when NP4 was used. Relatively lower surface energy of NP4 among three surfactants would induce spatial distribution of NP4 on the hydrophobic surface of Polyvinyl Siloxane and consequently resulted in higher surfactant concentration on the surface of the silicone impression material. The surfactant dispersion size also seemed to be relevant for the surface activation in these surfactant-modified silicone impression materials. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2395–2401, 2004
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Mechanism study on surface activation of surfactant‐modified Polyvinyl Siloxane impression materials
Journal of Applied Polymer Science, 2004Co-Authors: Doug-youn Lee, Kwang-mahn Kim, Kyung Ho Chung, Kyoung-nam KimAbstract:This study examined the mechanism on the surface activation of hydrophilic Polyvinyl Siloxane impression materials incorporated with nonionic surfactants. Hydrophilic Polyvinyl Siloxane impression materials were prepared with a polydimethylSiloxane composition and nonionic surfactants. The surfactants used were nonylphenoxy poly(ethyleneoxy) ethanol homologs of varying ethyleneoxy chain length. These homologs were designated NP4, NP6, and NP10 according to the mole number of ethyleneoxy group (hydrophilic group) of 4, 6, and 10, respectively. The incorporation of a nonionic surfactant into Polyvinyl Siloxanes enhanced their hydrophilicity and consequently led to the significant reduction in the contact angles. The higher the concentration of surfactant that was incorporated, the lower the contact angles that were observed. The contact angle was lowest when NP4 was incorporated, even though NP4 is less hydrophilic than NP6 and NP10, which implies that the exposed surfactant concentration on the surface was highest when NP4 was used. Relatively lower surface energy of NP4 among three surfactants would induce spatial distribution of NP4 on the hydrophobic surface of Polyvinyl Siloxane and consequently resulted in higher surfactant concentration on the surface of the silicone impression material. The surfactant dispersion size also seemed to be relevant for the surface activation in these surfactant-modified silicone impression materials. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2395–2401, 2004
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Effect of non-ionic surfactants on surface properties of hydrophilic Polyvinyl Siloxane impression materials
Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2003Co-Authors: Doug-youn Lee, Sooyoung Hwang, Kyoung-nam Kim, Kwang-mahn KimAbstract:Abstract This study examines the effect of non-ionic surfactants on surface hydrophilicity and detail reproducibility of die stone for hydrophilic Polyvinyl Siloxane impression materials. Hydrophilic Polyvinyl Siloxane impression materials were prepared with a polydimethylSiloxane composition and non-ionic surfactants. The surfactants used were nonylphenoxy poly(ethyleneoxy) ethanol homologs of varying ethyleneoxy chain length. These homologs are designated NP4, NP6, and NP10 according to the mole number of ethyleneoxy group of 4, 6, and 10, respectively. The contact angle, consistency, linear dimensional accuracy, and detail reproducibility for hydrophilic Polyvinyl Siloxane impression materials were tested. The non-ionic surfactants used in this study contain a silicone-loving group (nonylphenoxy group) which makes the surfactant dispersible in the silicone prepolymer. The dispersion size of these surfactants in Polyvinyl Siloxane prepolymers was dependent on the HLB of each surfactant. The more hydrophobic (silicone-loving) a surfactant is, the smaller the dispersion size is obtained. The incorporation of non-ionic surfactant into Polyvinyl Siloxanes enhanced their surface hydrophilicity and consequently led to significant reduction in contact angles. Significant differences in contact angle were found among the samples (P
Doug-youn Lee - One of the best experts on this subject based on the ideXlab platform.
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mechanism study on surface activation of surfactant modified Polyvinyl Siloxane impression materials
Journal of Applied Polymer Science, 2004Co-Authors: Doug-youn Lee, Kwang-mahn Kim, Kyung Ho Chung, Kyoung-nam KimAbstract:This study examined the mechanism on the surface activation of hydrophilic Polyvinyl Siloxane impression materials incorporated with nonionic surfactants. Hydrophilic Polyvinyl Siloxane impression materials were prepared with a polydimethylSiloxane composition and nonionic surfactants. The surfactants used were nonylphenoxy poly(ethyleneoxy) ethanol homologs of varying ethyleneoxy chain length. These homologs were designated NP4, NP6, and NP10 according to the mole number of ethyleneoxy group (hydrophilic group) of 4, 6, and 10, respectively. The incorporation of a nonionic surfactant into Polyvinyl Siloxanes enhanced their hydrophilicity and consequently led to the significant reduction in the contact angles. The higher the concentration of surfactant that was incorporated, the lower the contact angles that were observed. The contact angle was lowest when NP4 was incorporated, even though NP4 is less hydrophilic than NP6 and NP10, which implies that the exposed surfactant concentration on the surface was highest when NP4 was used. Relatively lower surface energy of NP4 among three surfactants would induce spatial distribution of NP4 on the hydrophobic surface of Polyvinyl Siloxane and consequently resulted in higher surfactant concentration on the surface of the silicone impression material. The surfactant dispersion size also seemed to be relevant for the surface activation in these surfactant-modified silicone impression materials. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2395–2401, 2004
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Mechanism study on surface activation of surfactant‐modified Polyvinyl Siloxane impression materials
Journal of Applied Polymer Science, 2004Co-Authors: Doug-youn Lee, Kwang-mahn Kim, Kyung Ho Chung, Kyoung-nam KimAbstract:This study examined the mechanism on the surface activation of hydrophilic Polyvinyl Siloxane impression materials incorporated with nonionic surfactants. Hydrophilic Polyvinyl Siloxane impression materials were prepared with a polydimethylSiloxane composition and nonionic surfactants. The surfactants used were nonylphenoxy poly(ethyleneoxy) ethanol homologs of varying ethyleneoxy chain length. These homologs were designated NP4, NP6, and NP10 according to the mole number of ethyleneoxy group (hydrophilic group) of 4, 6, and 10, respectively. The incorporation of a nonionic surfactant into Polyvinyl Siloxanes enhanced their hydrophilicity and consequently led to the significant reduction in the contact angles. The higher the concentration of surfactant that was incorporated, the lower the contact angles that were observed. The contact angle was lowest when NP4 was incorporated, even though NP4 is less hydrophilic than NP6 and NP10, which implies that the exposed surfactant concentration on the surface was highest when NP4 was used. Relatively lower surface energy of NP4 among three surfactants would induce spatial distribution of NP4 on the hydrophobic surface of Polyvinyl Siloxane and consequently resulted in higher surfactant concentration on the surface of the silicone impression material. The surfactant dispersion size also seemed to be relevant for the surface activation in these surfactant-modified silicone impression materials. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2395–2401, 2004
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Effect of non-ionic surfactants on surface properties of hydrophilic Polyvinyl Siloxane impression materials
Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2003Co-Authors: Doug-youn Lee, Sooyoung Hwang, Kyoung-nam Kim, Kwang-mahn KimAbstract:Abstract This study examines the effect of non-ionic surfactants on surface hydrophilicity and detail reproducibility of die stone for hydrophilic Polyvinyl Siloxane impression materials. Hydrophilic Polyvinyl Siloxane impression materials were prepared with a polydimethylSiloxane composition and non-ionic surfactants. The surfactants used were nonylphenoxy poly(ethyleneoxy) ethanol homologs of varying ethyleneoxy chain length. These homologs are designated NP4, NP6, and NP10 according to the mole number of ethyleneoxy group of 4, 6, and 10, respectively. The contact angle, consistency, linear dimensional accuracy, and detail reproducibility for hydrophilic Polyvinyl Siloxane impression materials were tested. The non-ionic surfactants used in this study contain a silicone-loving group (nonylphenoxy group) which makes the surfactant dispersible in the silicone prepolymer. The dispersion size of these surfactants in Polyvinyl Siloxane prepolymers was dependent on the HLB of each surfactant. The more hydrophobic (silicone-loving) a surfactant is, the smaller the dispersion size is obtained. The incorporation of non-ionic surfactant into Polyvinyl Siloxanes enhanced their surface hydrophilicity and consequently led to significant reduction in contact angles. Significant differences in contact angle were found among the samples (P
Kyoung-nam Kim - One of the best experts on this subject based on the ideXlab platform.
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mechanism study on surface activation of surfactant modified Polyvinyl Siloxane impression materials
Journal of Applied Polymer Science, 2004Co-Authors: Doug-youn Lee, Kwang-mahn Kim, Kyung Ho Chung, Kyoung-nam KimAbstract:This study examined the mechanism on the surface activation of hydrophilic Polyvinyl Siloxane impression materials incorporated with nonionic surfactants. Hydrophilic Polyvinyl Siloxane impression materials were prepared with a polydimethylSiloxane composition and nonionic surfactants. The surfactants used were nonylphenoxy poly(ethyleneoxy) ethanol homologs of varying ethyleneoxy chain length. These homologs were designated NP4, NP6, and NP10 according to the mole number of ethyleneoxy group (hydrophilic group) of 4, 6, and 10, respectively. The incorporation of a nonionic surfactant into Polyvinyl Siloxanes enhanced their hydrophilicity and consequently led to the significant reduction in the contact angles. The higher the concentration of surfactant that was incorporated, the lower the contact angles that were observed. The contact angle was lowest when NP4 was incorporated, even though NP4 is less hydrophilic than NP6 and NP10, which implies that the exposed surfactant concentration on the surface was highest when NP4 was used. Relatively lower surface energy of NP4 among three surfactants would induce spatial distribution of NP4 on the hydrophobic surface of Polyvinyl Siloxane and consequently resulted in higher surfactant concentration on the surface of the silicone impression material. The surfactant dispersion size also seemed to be relevant for the surface activation in these surfactant-modified silicone impression materials. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2395–2401, 2004
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Mechanism study on surface activation of surfactant‐modified Polyvinyl Siloxane impression materials
Journal of Applied Polymer Science, 2004Co-Authors: Doug-youn Lee, Kwang-mahn Kim, Kyung Ho Chung, Kyoung-nam KimAbstract:This study examined the mechanism on the surface activation of hydrophilic Polyvinyl Siloxane impression materials incorporated with nonionic surfactants. Hydrophilic Polyvinyl Siloxane impression materials were prepared with a polydimethylSiloxane composition and nonionic surfactants. The surfactants used were nonylphenoxy poly(ethyleneoxy) ethanol homologs of varying ethyleneoxy chain length. These homologs were designated NP4, NP6, and NP10 according to the mole number of ethyleneoxy group (hydrophilic group) of 4, 6, and 10, respectively. The incorporation of a nonionic surfactant into Polyvinyl Siloxanes enhanced their hydrophilicity and consequently led to the significant reduction in the contact angles. The higher the concentration of surfactant that was incorporated, the lower the contact angles that were observed. The contact angle was lowest when NP4 was incorporated, even though NP4 is less hydrophilic than NP6 and NP10, which implies that the exposed surfactant concentration on the surface was highest when NP4 was used. Relatively lower surface energy of NP4 among three surfactants would induce spatial distribution of NP4 on the hydrophobic surface of Polyvinyl Siloxane and consequently resulted in higher surfactant concentration on the surface of the silicone impression material. The surfactant dispersion size also seemed to be relevant for the surface activation in these surfactant-modified silicone impression materials. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2395–2401, 2004
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Effect of non-ionic surfactants on surface properties of hydrophilic Polyvinyl Siloxane impression materials
Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2003Co-Authors: Doug-youn Lee, Sooyoung Hwang, Kyoung-nam Kim, Kwang-mahn KimAbstract:Abstract This study examines the effect of non-ionic surfactants on surface hydrophilicity and detail reproducibility of die stone for hydrophilic Polyvinyl Siloxane impression materials. Hydrophilic Polyvinyl Siloxane impression materials were prepared with a polydimethylSiloxane composition and non-ionic surfactants. The surfactants used were nonylphenoxy poly(ethyleneoxy) ethanol homologs of varying ethyleneoxy chain length. These homologs are designated NP4, NP6, and NP10 according to the mole number of ethyleneoxy group of 4, 6, and 10, respectively. The contact angle, consistency, linear dimensional accuracy, and detail reproducibility for hydrophilic Polyvinyl Siloxane impression materials were tested. The non-ionic surfactants used in this study contain a silicone-loving group (nonylphenoxy group) which makes the surfactant dispersible in the silicone prepolymer. The dispersion size of these surfactants in Polyvinyl Siloxane prepolymers was dependent on the HLB of each surfactant. The more hydrophobic (silicone-loving) a surfactant is, the smaller the dispersion size is obtained. The incorporation of non-ionic surfactant into Polyvinyl Siloxanes enhanced their surface hydrophilicity and consequently led to significant reduction in contact angles. Significant differences in contact angle were found among the samples (P
In Aparna - One of the best experts on this subject based on the ideXlab platform.
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Effect of frequency and amplitude of vibration and role of a surfactant on void formation in models poured from Polyvinyl Siloxane impressions
Journal of conservative dentistry : JCD, 2011Co-Authors: N Kulashekar Reddy, In AparnaAbstract:Aims : To determine whether the frequency and amplitude of vibration and the use of surfactant has any effect on the formation of voids on the cast surface, poured from a Polyvinyl Siloxane impression material, using a mechanical model vibrator. Materials and Methods : A total of 100 impressions of a master die were made using Reprosil, Type 1, Medium Viscosity, Regular body, and Dentsply Caulk. The test group was subdivided into a surfactant and non-surfactant group, 50 impressions each. The impressions were poured in a dental stone with a mechanical model vibrator that was set at a vibration frequency of 3000 cycles / minute (low) and 6000 cycles / minute (high) with the help of a knob. The resultant casts were examined with a Stereomicroscope (LABOMED CZM4) under x10 magnifications. Results : For the low and high frequencies, when surfactant and non-surfactant groups were compared, for all the amplitudes and for both the material groups, the surfactant groups resulted in fewer void formations and showed very high statistical significance (P-value = 0.001). Conclusions : The lowest mean voids were obtained for high frequency surfactant groups. Reprosil: High frequency amplitude 2 being the most prominent, produced the least mean voids (mean = 23.2000, P = 0.001, very highly significant). In comparison, the surfactant groups produced the least voids for both frequencies.
N Kulashekar Reddy - One of the best experts on this subject based on the ideXlab platform.
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Effect of frequency and amplitude of vibration and role of a surfactant on void formation in models poured from Polyvinyl Siloxane impressions
Journal of conservative dentistry : JCD, 2011Co-Authors: N Kulashekar Reddy, In AparnaAbstract:Aims : To determine whether the frequency and amplitude of vibration and the use of surfactant has any effect on the formation of voids on the cast surface, poured from a Polyvinyl Siloxane impression material, using a mechanical model vibrator. Materials and Methods : A total of 100 impressions of a master die were made using Reprosil, Type 1, Medium Viscosity, Regular body, and Dentsply Caulk. The test group was subdivided into a surfactant and non-surfactant group, 50 impressions each. The impressions were poured in a dental stone with a mechanical model vibrator that was set at a vibration frequency of 3000 cycles / minute (low) and 6000 cycles / minute (high) with the help of a knob. The resultant casts were examined with a Stereomicroscope (LABOMED CZM4) under x10 magnifications. Results : For the low and high frequencies, when surfactant and non-surfactant groups were compared, for all the amplitudes and for both the material groups, the surfactant groups resulted in fewer void formations and showed very high statistical significance (P-value = 0.001). Conclusions : The lowest mean voids were obtained for high frequency surfactant groups. Reprosil: High frequency amplitude 2 being the most prominent, produced the least mean voids (mean = 23.2000, P = 0.001, very highly significant). In comparison, the surfactant groups produced the least voids for both frequencies.