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David C. Watts - One of the best experts on this subject based on the ideXlab platform.
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Effect of Filler Particles morphology of resin-composites on cavity packing force for repeated condensation
Dental materials journal, 2017Co-Authors: Muhammad Kaleem, David C. WattsAbstract:Effect of variation in morphology and size of Filler Particles, temperature and increase in condensation speed on packability of resincomposites was investigated. Eight experimental light-cured resin-composites (RZDn series) were tested. Each material was placed in a cylindrical mould at 26 or 32oC. A flat-ended stainless-steel probe (φ=6 mm) was mechanically lowered with two different speeds 2 and 8 mm/s onto and into at the surface of the unset sample until a compressive force of 1 N was reached. This was repeated for five cycles, and from each cycle Fp was calculated. All spherical and irregular Filler Particle resin-composites showed a decrease in Fp with increase in number of compressions. Increase in temperature also decreased Fp, but this effect was not very prominent in the case of irregular Filler resin-composites. Filler Particle morphology, increase in temperature and compression cycle speed has a prominent effect on packability of resin-composites.
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Effect of resin-composite Filler Particle size and shape on shrinkage-stress
Dental Materials, 2012Co-Authors: Julian D. Satterthwaite, Amit Maisuria, Karin Vogel, David C. WattsAbstract:Abstract Objectives The aim of this study was to investigate the effect of variations in Filler Particle size and shape on the polymerization shrinkage-stress kinetics of resin-composites. Methods A model series of 12 VLC resin-composites were studied. The particulate dispersed phase volume fraction was 56.7%: these Filler Particles were systematically graded in size, and further were either spherical or irregular. A Bioman instrument (cantilever beam method) was employed to determine the shrinkage-stress kinetics following 40 s irradiation (600 mW/cm 2 ) at 23 °C ( n = 3). All data were captured for 60 min and the final shrinkage-stress calculated. Results Shrinkage-stress varied between 3.86 MPa (SD 0.14) for S3 (spherical Filler Particles of 500 nm) and 8.44 MPa (SD 0.41) for I1 (irregular Filler Particles of 450 nm). The shrinkage-stress values were generally lower for those composites with spherical Filler Particles than those with irregular Filler Particles. The differences in shrinkage-stress with Filler Particle size and shape were statistically significant ( p Significance Composites with spherical Filler Particles exhibit lower shrinkage-stress values compared to those with irregular Filler Particles. Shrinkage-stress and shrinkage-stress rate vary in a complex manner with variations in the size of the dispersed phase Particles: a hypothesized explanation for the effect of Filler Particle size and shape is presented.
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Effect of resin-composite Filler Particle size and shape on shrinkage-stress.
Dental materials : official publication of the Academy of Dental Materials, 2012Co-Authors: Julian D. Satterthwaite, Amit Maisuria, Karin Vogel, David C. WattsAbstract:The aim of this study was to investigate the effect of variations in Filler Particle size and shape on the polymerization shrinkage-stress kinetics of resin-composites. A model series of 12 VLC resin-composites were studied. The particulate dispersed phase volume fraction was 56.7%: these Filler Particles were systematically graded in size, and further were either spherical or irregular. A Bioman instrument (cantilever beam method) was employed to determine the shrinkage-stress kinetics following 40s irradiation (600 mW/cm(2)) at 23°C (n=3). All data were captured for 60 min and the final shrinkage-stress calculated. Shrinkage-stress varied between 3.86 MPa (SD 0.14) for S3 (spherical Filler Particles of 500 nm) and 8.44 MPa (SD 0.41) for I1 (irregular Filler Particles of 450 nm). The shrinkage-stress values were generally lower for those composites with spherical Filler Particles than those with irregular Filler Particles. The differences in shrinkage-stress with Filler Particle size and shape were statistically significant (p<0.001). Composites with spherical Filler Particles exhibit lower shrinkage-stress values compared to those with irregular Filler Particles. Shrinkage-stress and shrinkage-stress rate vary in a complex manner with variations in the size of the dispersed phase Particles: a hypothesized explanation for the effect of Filler Particle size and shape is presented. Copyright © 2012 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.
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effect of resin composite Filler Particle size and shape on shrinkage strain
Dental Materials, 2009Co-Authors: Julian D. Satterthwaite, Amit Maisuria, Karin Vogel, David C. WattsAbstract:Abstract Objectives The aim of this study was to investigate the effect of variations in Filler Particle size and shape on the polymerization shrinkage-stress kinetics of resin-composites. Methods A model series of 12 VLC resin-composites were studied. The particulate dispersed phase volume fraction was 56.7%: these Filler Particles were systematically graded in size, and further were either spherical or irregular. A Bioman instrument (cantilever beam method) was employed to determine the shrinkage-stress kinetics following 40 s irradiation (600 mW/cm 2 ) at 23 °C ( n = 3). All data were captured for 60 min and the final shrinkage-stress calculated. Results Shrinkage-stress varied between 3.86 MPa (SD 0.14) for S3 (spherical Filler Particles of 500 nm) and 8.44 MPa (SD 0.41) for I1 (irregular Filler Particles of 450 nm). The shrinkage-stress values were generally lower for those composites with spherical Filler Particles than those with irregular Filler Particles. The differences in shrinkage-stress with Filler Particle size and shape were statistically significant ( p Significance Composites with spherical Filler Particles exhibit lower shrinkage-stress values compared to those with irregular Filler Particles. Shrinkage-stress and shrinkage-stress rate vary in a complex manner with variations in the size of the dispersed phase Particles: a hypothesized explanation for the effect of Filler Particle size and shape is presented.
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Effect of Filler Particle size and morphology on force/work parameters for stickiness of unset resin-composites.
Dental materials : official publication of the Academy of Dental Materials, 2009Co-Authors: Muhammad Kaleem, Julian D. Satterthwaite, David C. WattsAbstract:Abstract Objectives To investigate the effect of variation in Filler Particle size and morphology within an unset model series of resin-composites on two stickiness parameters: (1) maximum probe separation-force and (2) work-of-separation. This study was to complement previously reported measurements of composite stickiness in terms of a strain-parameter, ‘peak-height’. Materials and methods Eleven experimental light cured resin-composites were selected. All had the same matrix (Bis-GMA, UDMA and TEGDMA, with 0.33% camphoroquinone) and the same Filler volume fraction—56.7%, however Filler Particles varied in size and shape and were either unimodal or multimodal in size-distribution. Each material was placed in a cylindrical mould (φ = 7 mm × 5 mm depth) held at 26 or 37 °C. The maximum force (Fmax, N) and work of probe-separation (Ws, N mm) were measured. A flat-ended stainless-steel probe (φ = 6 mm) was mechanically lowered onto and into the surface of the unset sample, until a compressive force of 1 N was reached, which was held constant for 1 s. Then the probe was moved vertically upward at a constant speed; either 2 or 8 mm/s. The tensile force produced on the probe by the sticky composite was plotted against displacement and the maximum value was identified (Fmax). Ws was obtained as the integrated area. Data was analyzed by multivariate ANOVA and multiple pair-wise comparisons using a Tukey post hoc test to establish homogenous subsets (at p = 0.05) for Fmax and a Games–Howell was used for Ws. Results As potential measures of stickiness, Fmax and Ws showed more coherent trends with Fillersize when measured at the lower of the two probe speeds, 2 mm/s. For unimodal resin-composite Fmax ranged from 1.04 to 5.11 N and Ws from 0.48 to 11.12 N mm. For the multimodal resin-composite they ranged from 1.64 to 4.13 N and from 2.32 to 8.34 N mm respectively. Temperature increase tended to slightly reduce Fmax, although this trend was not consistent. Ws generally increased with temperature. Conclusion Filler Particle size and morphology influences Fmax and Ws of uncured resin-composite which partly express the handling behaviors of resin-composites.
Julian D. Satterthwaite - One of the best experts on this subject based on the ideXlab platform.
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Effect of resin-composite Filler Particle size and shape on shrinkage-stress
Dental Materials, 2012Co-Authors: Julian D. Satterthwaite, Amit Maisuria, Karin Vogel, David C. WattsAbstract:Abstract Objectives The aim of this study was to investigate the effect of variations in Filler Particle size and shape on the polymerization shrinkage-stress kinetics of resin-composites. Methods A model series of 12 VLC resin-composites were studied. The particulate dispersed phase volume fraction was 56.7%: these Filler Particles were systematically graded in size, and further were either spherical or irregular. A Bioman instrument (cantilever beam method) was employed to determine the shrinkage-stress kinetics following 40 s irradiation (600 mW/cm 2 ) at 23 °C ( n = 3). All data were captured for 60 min and the final shrinkage-stress calculated. Results Shrinkage-stress varied between 3.86 MPa (SD 0.14) for S3 (spherical Filler Particles of 500 nm) and 8.44 MPa (SD 0.41) for I1 (irregular Filler Particles of 450 nm). The shrinkage-stress values were generally lower for those composites with spherical Filler Particles than those with irregular Filler Particles. The differences in shrinkage-stress with Filler Particle size and shape were statistically significant ( p Significance Composites with spherical Filler Particles exhibit lower shrinkage-stress values compared to those with irregular Filler Particles. Shrinkage-stress and shrinkage-stress rate vary in a complex manner with variations in the size of the dispersed phase Particles: a hypothesized explanation for the effect of Filler Particle size and shape is presented.
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Effect of resin-composite Filler Particle size and shape on shrinkage-stress.
Dental materials : official publication of the Academy of Dental Materials, 2012Co-Authors: Julian D. Satterthwaite, Amit Maisuria, Karin Vogel, David C. WattsAbstract:The aim of this study was to investigate the effect of variations in Filler Particle size and shape on the polymerization shrinkage-stress kinetics of resin-composites. A model series of 12 VLC resin-composites were studied. The particulate dispersed phase volume fraction was 56.7%: these Filler Particles were systematically graded in size, and further were either spherical or irregular. A Bioman instrument (cantilever beam method) was employed to determine the shrinkage-stress kinetics following 40s irradiation (600 mW/cm(2)) at 23°C (n=3). All data were captured for 60 min and the final shrinkage-stress calculated. Shrinkage-stress varied between 3.86 MPa (SD 0.14) for S3 (spherical Filler Particles of 500 nm) and 8.44 MPa (SD 0.41) for I1 (irregular Filler Particles of 450 nm). The shrinkage-stress values were generally lower for those composites with spherical Filler Particles than those with irregular Filler Particles. The differences in shrinkage-stress with Filler Particle size and shape were statistically significant (p<0.001). Composites with spherical Filler Particles exhibit lower shrinkage-stress values compared to those with irregular Filler Particles. Shrinkage-stress and shrinkage-stress rate vary in a complex manner with variations in the size of the dispersed phase Particles: a hypothesized explanation for the effect of Filler Particle size and shape is presented. Copyright © 2012 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.
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effect of resin composite Filler Particle size and shape on shrinkage strain
Dental Materials, 2009Co-Authors: Julian D. Satterthwaite, Amit Maisuria, Karin Vogel, David C. WattsAbstract:Abstract Objectives The aim of this study was to investigate the effect of variations in Filler Particle size and shape on the polymerization shrinkage-stress kinetics of resin-composites. Methods A model series of 12 VLC resin-composites were studied. The particulate dispersed phase volume fraction was 56.7%: these Filler Particles were systematically graded in size, and further were either spherical or irregular. A Bioman instrument (cantilever beam method) was employed to determine the shrinkage-stress kinetics following 40 s irradiation (600 mW/cm 2 ) at 23 °C ( n = 3). All data were captured for 60 min and the final shrinkage-stress calculated. Results Shrinkage-stress varied between 3.86 MPa (SD 0.14) for S3 (spherical Filler Particles of 500 nm) and 8.44 MPa (SD 0.41) for I1 (irregular Filler Particles of 450 nm). The shrinkage-stress values were generally lower for those composites with spherical Filler Particles than those with irregular Filler Particles. The differences in shrinkage-stress with Filler Particle size and shape were statistically significant ( p Significance Composites with spherical Filler Particles exhibit lower shrinkage-stress values compared to those with irregular Filler Particles. Shrinkage-stress and shrinkage-stress rate vary in a complex manner with variations in the size of the dispersed phase Particles: a hypothesized explanation for the effect of Filler Particle size and shape is presented.
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effect of Filler Particle size and morphology on force work parameters for stickiness of unset resin composites
Dental Materials, 2009Co-Authors: Julian D. Satterthwaite, Muhammad Kaleem, D C WattsAbstract:Abstract Objectives To investigate the effect of variation in Filler Particle size and morphology within an unset model series of resin-composites on two stickiness parameters: (1) maximum probe separation-force and (2) work-of-separation. This study was to complement previously reported measurements of composite stickiness in terms of a strain-parameter, ‘peak-height’. Materials and methods Eleven experimental light cured resin-composites were selected. All had the same matrix (Bis-GMA, UDMA and TEGDMA, with 0.33% camphoroquinone) and the same Filler volume fraction—56.7%, however Filler Particles varied in size and shape and were either unimodal or multimodal in size-distribution. Each material was placed in a cylindrical mould (φ = 7 mm × 5 mm depth) held at 26 or 37 °C. The maximum force (Fmax, N) and work of probe-separation (Ws, N mm) were measured. A flat-ended stainless-steel probe (φ = 6 mm) was mechanically lowered onto and into the surface of the unset sample, until a compressive force of 1 N was reached, which was held constant for 1 s. Then the probe was moved vertically upward at a constant speed; either 2 or 8 mm/s. The tensile force produced on the probe by the sticky composite was plotted against displacement and the maximum value was identified (Fmax). Ws was obtained as the integrated area. Data was analyzed by multivariate ANOVA and multiple pair-wise comparisons using a Tukey post hoc test to establish homogenous subsets (at p = 0.05) for Fmax and a Games–Howell was used for Ws. Results As potential measures of stickiness, Fmax and Ws showed more coherent trends with Fillersize when measured at the lower of the two probe speeds, 2 mm/s. For unimodal resin-composite Fmax ranged from 1.04 to 5.11 N and Ws from 0.48 to 11.12 N mm. For the multimodal resin-composite they ranged from 1.64 to 4.13 N and from 2.32 to 8.34 N mm respectively. Temperature increase tended to slightly reduce Fmax, although this trend was not consistent. Ws generally increased with temperature. Conclusion Filler Particle size and morphology influences Fmax and Ws of uncured resin-composite which partly express the handling behaviors of resin-composites.
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Effect of Filler Particle size and morphology on force/work parameters for stickiness of unset resin-composites.
Dental materials : official publication of the Academy of Dental Materials, 2009Co-Authors: Muhammad Kaleem, Julian D. Satterthwaite, David C. WattsAbstract:Abstract Objectives To investigate the effect of variation in Filler Particle size and morphology within an unset model series of resin-composites on two stickiness parameters: (1) maximum probe separation-force and (2) work-of-separation. This study was to complement previously reported measurements of composite stickiness in terms of a strain-parameter, ‘peak-height’. Materials and methods Eleven experimental light cured resin-composites were selected. All had the same matrix (Bis-GMA, UDMA and TEGDMA, with 0.33% camphoroquinone) and the same Filler volume fraction—56.7%, however Filler Particles varied in size and shape and were either unimodal or multimodal in size-distribution. Each material was placed in a cylindrical mould (φ = 7 mm × 5 mm depth) held at 26 or 37 °C. The maximum force (Fmax, N) and work of probe-separation (Ws, N mm) were measured. A flat-ended stainless-steel probe (φ = 6 mm) was mechanically lowered onto and into the surface of the unset sample, until a compressive force of 1 N was reached, which was held constant for 1 s. Then the probe was moved vertically upward at a constant speed; either 2 or 8 mm/s. The tensile force produced on the probe by the sticky composite was plotted against displacement and the maximum value was identified (Fmax). Ws was obtained as the integrated area. Data was analyzed by multivariate ANOVA and multiple pair-wise comparisons using a Tukey post hoc test to establish homogenous subsets (at p = 0.05) for Fmax and a Games–Howell was used for Ws. Results As potential measures of stickiness, Fmax and Ws showed more coherent trends with Fillersize when measured at the lower of the two probe speeds, 2 mm/s. For unimodal resin-composite Fmax ranged from 1.04 to 5.11 N and Ws from 0.48 to 11.12 N mm. For the multimodal resin-composite they ranged from 1.64 to 4.13 N and from 2.32 to 8.34 N mm respectively. Temperature increase tended to slightly reduce Fmax, although this trend was not consistent. Ws generally increased with temperature. Conclusion Filler Particle size and morphology influences Fmax and Ws of uncured resin-composite which partly express the handling behaviors of resin-composites.
Muhammad Kaleem - One of the best experts on this subject based on the ideXlab platform.
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Effect of Filler Particles morphology of resin-composites on cavity packing force for repeated condensation
Dental materials journal, 2017Co-Authors: Muhammad Kaleem, David C. WattsAbstract:Effect of variation in morphology and size of Filler Particles, temperature and increase in condensation speed on packability of resincomposites was investigated. Eight experimental light-cured resin-composites (RZDn series) were tested. Each material was placed in a cylindrical mould at 26 or 32oC. A flat-ended stainless-steel probe (φ=6 mm) was mechanically lowered with two different speeds 2 and 8 mm/s onto and into at the surface of the unset sample until a compressive force of 1 N was reached. This was repeated for five cycles, and from each cycle Fp was calculated. All spherical and irregular Filler Particle resin-composites showed a decrease in Fp with increase in number of compressions. Increase in temperature also decreased Fp, but this effect was not very prominent in the case of irregular Filler resin-composites. Filler Particle morphology, increase in temperature and compression cycle speed has a prominent effect on packability of resin-composites.
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effect of Filler Particle size and morphology on force work parameters for stickiness of unset resin composites
Dental Materials, 2009Co-Authors: Julian D. Satterthwaite, Muhammad Kaleem, D C WattsAbstract:Abstract Objectives To investigate the effect of variation in Filler Particle size and morphology within an unset model series of resin-composites on two stickiness parameters: (1) maximum probe separation-force and (2) work-of-separation. This study was to complement previously reported measurements of composite stickiness in terms of a strain-parameter, ‘peak-height’. Materials and methods Eleven experimental light cured resin-composites were selected. All had the same matrix (Bis-GMA, UDMA and TEGDMA, with 0.33% camphoroquinone) and the same Filler volume fraction—56.7%, however Filler Particles varied in size and shape and were either unimodal or multimodal in size-distribution. Each material was placed in a cylindrical mould (φ = 7 mm × 5 mm depth) held at 26 or 37 °C. The maximum force (Fmax, N) and work of probe-separation (Ws, N mm) were measured. A flat-ended stainless-steel probe (φ = 6 mm) was mechanically lowered onto and into the surface of the unset sample, until a compressive force of 1 N was reached, which was held constant for 1 s. Then the probe was moved vertically upward at a constant speed; either 2 or 8 mm/s. The tensile force produced on the probe by the sticky composite was plotted against displacement and the maximum value was identified (Fmax). Ws was obtained as the integrated area. Data was analyzed by multivariate ANOVA and multiple pair-wise comparisons using a Tukey post hoc test to establish homogenous subsets (at p = 0.05) for Fmax and a Games–Howell was used for Ws. Results As potential measures of stickiness, Fmax and Ws showed more coherent trends with Fillersize when measured at the lower of the two probe speeds, 2 mm/s. For unimodal resin-composite Fmax ranged from 1.04 to 5.11 N and Ws from 0.48 to 11.12 N mm. For the multimodal resin-composite they ranged from 1.64 to 4.13 N and from 2.32 to 8.34 N mm respectively. Temperature increase tended to slightly reduce Fmax, although this trend was not consistent. Ws generally increased with temperature. Conclusion Filler Particle size and morphology influences Fmax and Ws of uncured resin-composite which partly express the handling behaviors of resin-composites.
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Effect of Filler Particle size and morphology on force/work parameters for stickiness of unset resin-composites.
Dental materials : official publication of the Academy of Dental Materials, 2009Co-Authors: Muhammad Kaleem, Julian D. Satterthwaite, David C. WattsAbstract:Abstract Objectives To investigate the effect of variation in Filler Particle size and morphology within an unset model series of resin-composites on two stickiness parameters: (1) maximum probe separation-force and (2) work-of-separation. This study was to complement previously reported measurements of composite stickiness in terms of a strain-parameter, ‘peak-height’. Materials and methods Eleven experimental light cured resin-composites were selected. All had the same matrix (Bis-GMA, UDMA and TEGDMA, with 0.33% camphoroquinone) and the same Filler volume fraction—56.7%, however Filler Particles varied in size and shape and were either unimodal or multimodal in size-distribution. Each material was placed in a cylindrical mould (φ = 7 mm × 5 mm depth) held at 26 or 37 °C. The maximum force (Fmax, N) and work of probe-separation (Ws, N mm) were measured. A flat-ended stainless-steel probe (φ = 6 mm) was mechanically lowered onto and into the surface of the unset sample, until a compressive force of 1 N was reached, which was held constant for 1 s. Then the probe was moved vertically upward at a constant speed; either 2 or 8 mm/s. The tensile force produced on the probe by the sticky composite was plotted against displacement and the maximum value was identified (Fmax). Ws was obtained as the integrated area. Data was analyzed by multivariate ANOVA and multiple pair-wise comparisons using a Tukey post hoc test to establish homogenous subsets (at p = 0.05) for Fmax and a Games–Howell was used for Ws. Results As potential measures of stickiness, Fmax and Ws showed more coherent trends with Fillersize when measured at the lower of the two probe speeds, 2 mm/s. For unimodal resin-composite Fmax ranged from 1.04 to 5.11 N and Ws from 0.48 to 11.12 N mm. For the multimodal resin-composite they ranged from 1.64 to 4.13 N and from 2.32 to 8.34 N mm respectively. Temperature increase tended to slightly reduce Fmax, although this trend was not consistent. Ws generally increased with temperature. Conclusion Filler Particle size and morphology influences Fmax and Ws of uncured resin-composite which partly express the handling behaviors of resin-composites.
Chengduo Qian - One of the best experts on this subject based on the ideXlab platform.
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Effects of Filler Particle size and ageing on the fatigue behaviour of bituminous mastics
Construction and Building Materials, 2020Co-Authors: Baodong Xing, Weiyu Fan, Ling Han, Chuanyi Zhuang, Chengduo QianAbstract:Abstract Fatigue cracking is caused by repeated traffic loads and environmental conditions (temperature, ageing, etc.); it predominantly initiates within the mastic phase in the form of micro-cracks. In this sense, bituminous mastics (comprised of a binder, Filler and entrapped air) play a significant role in the anti-fatigue performance of asphalt mixes. In this paper, the effects of Filler Particle size and ageing on the fatigue behaviour of bituminous mastics were evaluated. Prior to this, the rheological properties of the studied samples were evaluated using physical tests and frequency sweep tests. Moreover, the mastic morphology and Filler distribution inside a bituminous matrix were characterized by Scan Electronic Microscope (SEM). The results revealed that ageing had a greater effect than Filler Particle size on the rheological behaviour of SBS-modified bituminous mastics, especially for mastics containing coarse Filler Particles. According to the ageing responses derived from log-log fatigue law plots, aged mastics containing coarse Filler Particles had higher slopes (represented by coefficient B) and lower intercepts (identified by coefficient A) than un-aged mastics. However, opposite fatigue behaviour was observed with fine Filler granules, where coefficient B slightly decreased while coefficient A slightly increased after ageing. In addition, mastic morphology and Filler dispersion inside a bituminous matrix were characterized by SEM, providing insight to possible relationships between morphological characteristics and fatigue performance.
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effects of the morphological characteristics of mineral powder Fillers on the rheological properties of asphalt mastics at high and medium temperatures
Powder Technology, 2019Co-Authors: Baodong Xing, Weiyu Fan, Chuanyi Zhuang, Chengduo QianAbstract:Abstract The primary objective of this study was to investigate the feasibility of the dispersion of Fillers dispersion as individual Particles and evaluate the effects of the morphological characteristics of Filler Particles on the rheological properties of asphalt mastics at high and medium temperatures. For a given source and Filler, three various Filler Particle sizes produced from different crushers (i.e., a jaw crusher, an impact crusher and a ball grinding mill) were obtained, namely, F1 (P200-R300: passing a 200-mesh and retained by a 300-mesh sieve), F2 (P400-R500) and F3 (P800-R1000). The binary image Particle analysis system was employed to acquire the morphological characteristics of Filler Particles such as form factor, angularity and surface texture. By applying multiple stress creep and recovery (MSCR) tests at high temperature and time sweep (TS) tests at medium temperature, the rheological properties of asphalt mastics prepared with different Filler Particle sizes were also investigated. Furthermore, the correlations between the morphological characteristics of Filler Particles and the high/medium-temperature properties of asphalt mastics were studied by grey relational analysis (GRA) method. Results showed that the proposed new approach to sample preparation was demonstrated to be effective in achieving Filler Particle dispersion. The GRA demonstrated that the rheological properties of asphalt mastics at high and medium temperatures were significantly affected by the morphological characteristics of the Filler Particles. Percent recovery (R) and fatigue law fitting coefficients (A and B) were more sensitive to porosity, angularity index, average diameter, aspect ratio and fractal dimension but less sensitive to feature roughness, roundness, convexity ratio, density and specific surface area. In terms of non-recoverable creep compliance (Jnr), the sensibility was apparently reversed, with the reference sequence Jnr presenting less susceptibility to porosity, angularity index, average diameter, aspect ratio and fractal dimension. The GRA results can inform engineers regarding the selection of Filler Particles that produce asphalt mastics with desired performance characteristics, such as specific rutting resistance and fatigue failure.
Sharon C. Glotzer - One of the best experts on this subject based on the ideXlab platform.
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effects of a nanoscopic Filler on the structure and dynamics of a simulated polymer melt and the relationship to ultrathin films
Physical Review E, 2001Co-Authors: Francis W Starr, Thomas B Schroder, Sharon C. GlotzerAbstract:~Received 19 July 2000; revised manuscript received 9 January 2001; published 27 July 2001! We perform molecular dynamics simulations of an idealized polymer melt surrounding a nanoscopic Filler Particle. We show that the glass transition temperature Tg of the melt can be shifted to either higher or lower temperatures by tuning the interactions between polymer and Filler. A gradual change of the polymer dynamics approaching the Filler surface causes the change in the glass transition. We also find that polymers close to the surface tend to be elongated and flattened. Our findings show a strong similarity to those obtained for ultrathin polymer films.