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HOME > Restor Dent Endod > Volume 29(6); 2004 > Article
Original Article RHEOLOGICAL PROPERTIES OF RESIN COMPOSITES ACCORDING TO THE CHANGE OF MONOMER AND FILLER COMPOSITIONS
In-Bog Lee, Jong-Hyuck Lee, Byung-Hoon Cho, Sang-Tag Lee, Chung-Moon Um,1
J Korean Acad Conserv Dent 2004;29(6):-531.
DOI: https://doi.org/10.5395/JKACD.2004.29.6.520
Published online: January 14, 2004

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*Corresponding author: Chung-Moon Um, Department of Conservative Dentistry, College of Dentistry, Seoul National University 28 Yoengun-dong, Chongro-gu, Seoul, Korea, 110-749, Tel : 82-2-2072-3953, 2651 Fax : 82-2-2072-3859, E-mail : inboglee@snu.ac.kr

Copyright © 2004 The Korean Academy of Conservative Dentistry

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

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  • Objectives.
    The aim of this study was to investigate the effect of monomer and filler compositions on the rheological properties related to the handling characteristics of resin composites.
  • Methods.
    Resin matrices that Bis-GMA as base monomer was blended with TEGDMA as diluent at various ratio were mixed with the Barium glass (0.7 um and 1.0 um), 0.04 um fumed silica and 0.5 um round silica. All used fillers were silane treated. In order to vary the viscosity of experimental composites, the type and content of incorporated fillers were changed.
    Using a rheometer, a steady shear test and a dynamic oscillatory shear test were used to evaluate the viscosity (η) of resin matrix, and the storage shear modulus (G′), the loss shear modulus (G″), the loss tangent (tanδ) and the complex viscosity (η *) of the composites as a function of frequency ω = 0.1-100 rad/s. To investigate the effect of temperature on the viscosity of composites, a temperature sweep test was also undertaken.
  • Results.
    Resin matrices were Newtonian fluid regardless of diluent concentration and all experimental composites exhibited pseudoplastic behavior with increasing shear rate. The viscosity of composites was exponentially increased with increasing filler volume%. In the same filler volume, the smaller the fillers were used, the higher the viscosities were. The effect of filler size on the viscosity was increased with increasing filler content. Increasing filler content reduced tanδby increasing the G′further than the G″ . The viscosity of composites was decreased exponentially with increasing temperature.
Figure 1.
Relationship between shear storage modulus (G′), shear loss modulus (G″), complex shear modulus (G*) and loss tangent (tanδ) in a complex plane.
jkacd-29-520f1.jpg
Figure 2-a.
Viscosity of monomer blends of varying diluent’s concentration as a function of shear rates at 25℃.
jkacd-29-520f2a.jpg
Figure 2-b.
Steady shear viscosity, η, and dynamic complex viscosity, η*, of Bis-GMA only and Bis-GMA 6 : TEGDMA 4 blend at 25℃ and 35℃.
jkacd-29-520f2b.jpg
Figure 2-c.
Viscosity as a function of diluent fraction at temperature 25℃ and 35℃.
jkacd-29-520f2c.jpg
Figure 3-a.
Complex viscosity of experimental composites of varying filler contents (weight%) as a function of frequency.
jkacd-29-520f3a.jpg
Figure 3-b.
The effect of filler size and filler volume% on the complex viscosity of experimental composites at ω= 10 rad/s.
jkacd-29-520f3b.jpg
Figure 3-c.
Exponential regression curve, y = aebx, can be fitted on the complex viscosity of experimental composite with 0.5 um Silica as a function of filler volume fraction.
jkacd-29-520f3c.jpg
Figure 4-a.
The change of storage modulus G′and loss modulus G″with increasing filler content in 0.7um Ba glass.
jkacd-29-520f4a.jpg
Figure 4-b.
Loss tangent (Tanδ) of experimental composites as a function of filler volume %.
jkacd-29-520f4b.jpg
Figure 5.
Complex viscosity of experimental composites is exponentially decreased with increasing temperature.
jkacd-29-520f5.jpg
Figure 6.
Complex viscosity of experimental and commercial composites as a function of frequency.
jkacd-29-520f6.jpg
Figure 7-a.
Phasor representations of complex modulus G* and phase angle, δ, G*e= G*∠δ, of experimental and commercial composites at ω= 10 rad/s in a polar coordinate system.
jkacd-29-520f7a.jpg
Figure 7-b.
Locus of frequency domain phasor plots, G*(ω )e=G*(ω )∠δ, of composites at ω= 0.1 - 100 rad/s in a complex plane.
jkacd-29-520f7b.jpg
Table 1.
Monomers and inorganic fillers used to make experimental composites and commercial composites.
Monomers
  Bis-GMA 2,2-bis-[4-(methacryloxy-2-hydroxy-propoxy)-phenyl]-propane
Manufacturer; Aldrichi, Germany
  TEGDMA Triethylene glycol dimethacrylate
Manufacturer; Aldrichi, Germany
Inorganic fillers
  Filler Type Abbreviation Manufacturer
  1) 0.7 um barium glass irregular 0.7 um Ba Schott, Germany
  2) 1.0 um barium glass irregular 1.0 um Ba Schott, Germany
  3) 40 ㎚ fumed silica (Aerosil OX-50) round 0.04 um Silica Degussa, Germany
  4) 0.5 um silica round 0.5 um Silica Youthtech, Korea
Commercial Composite
  Z100 3M, USA
  Charisma Kulzer, Germany
  Clearfil Kuraray, Japan
  DenFil Vericom, Koreea
Table 2.
The experimental composites were made with various types, size and weight% (the unit of the numbers in the parenthesis are volume%) of fillers added to resin matrix (Bis-GMA 6 : TEGDMA 4).
(1) 0.7 um Ba
50 (30.3), 60 (39.5), 70 (50.4), 75 (56.7) wt%
(2) 1.0 um Ba
60 (39.5), 75 (56.7) wt%
(3) 0.04 um Silica
30 (19.7), 40 (27.6), 50 (36.4), 55.9 (42.1) wt%
(4) 0.5 um Silica
30 (19.3), 35 (23.1), 40 (27.1), 45 (31.3) wt%
(5) 0.7 um Ba 70 wt% + 0.04 um Silica 5 wt% - hybrid composite (57.2 vol%)
(6) 0.7 um Ba 65 wt% + 0.04um Silica 10 wt% - hybrid composite (57.7 vol%)
Table 3.
The shear viscosity of monomer blends at 25 ℃ and 35℃.
Monomer blends Shear viscosity (Pa.s)
Bis-GMA vs. TEGDMA 25 ℃ 35 ℃
Bis-GMA only 369 52.6
8 : 2 5.04 1.46
7 : 3 1.280 0.476
6 : 4 0.429 0.203
5 : 5 0.144 0.085
4 : 6 0.066 0.021
3 : 7 0.035 0.0213
2 : 8 0.022 0.014
TEGDMA only 0.0077 0.0068
Table 4.
The phasor presentation of complex modulus G* and phase angle δ, G*(ω )e=G*(ω )∠δ , and the complex viscosity η* of experimental and commercial composites at 25℃.
Composites G* (Pa) ∠ δ(°) η* (Pa.s)
ω= 0.1 rad/s ω= 1 rad/s ω= 10 rad/s ω= 10 rad/s
0.7 um Ba
  50 wt% 17.7 ∠ 55. 3 43.6 ∠ 58. 1 129.3 ∠ 72.3 12.9
  60 wt% 55.3 ∠ 43. 9 81.2 ∠ 53. 3 205.9∠ 69.5 20.6
  70 wt% 48.6 ∠ 39. 1 111.8 ∠ 48. 2 311.2 ∠ 67.1 31.1
  75 wt% 137.5 ∠ 40. 8 280.2 ∠ 44. 1 610.5 ∠ 61.1 61.1
1 um Ba
  60 wt% 5.3 ∠ 50. 2 23.3 ∠ 60. 9 108.4 ∠ 74.9 10.8
  75 wt% 46.7 ∠ 42. 4 117.1 ∠ 50. 7 348.1 ∠ 69.0 34.8
0.04 um Silica
  30 wt% 235.0 ∠ 53. 5 95.9 ∠ 62. 9 235.0 ∠ 71.7 23.5
  40 wt% 240.1 ∠ 61.34 768.2 ∠ 57. 9 1274.0 ∠ 65.1 127.4
  50 wt% 1792.8 ∠ 57. 4 2982.2 ∠ 48. 6 4179.0 ∠ 51.3 417.9
  55.9 wt% 6202.9 ∠ 42. 8 4710.4 ∠ 41. 8 6453.0 ∠ 43.7 645.3
0.5 um Silica
  30 wt% 4.0 ∠ 71. 0 14.4 ∠ 79. 0 65.4 ∠ 83.2 6.5
  35 wt% 9.0 ∠ 68. 9 23.5 ∠ 75. 6 91.9 ∠ 82.3 9.2
  40 wt% 18.9 ∠ 66. 3 42.9 ∠ 71. 0 120.9 ∠ 81.5 12.1
  45 wt% 39.0 ∠ 63. 1 74.8 ∠ 65. 2 169.8 ∠ 77.7 17.0
0.7 um Ba 70 wt% + 0.04 um Silica 5 wt%
370.3 ∠ 40. 5 690.6 ∠ 39. 0 1299.5 ∠ 49.3 129.9
0.7 um Ba 65 wt% + 0.04 um Silica 10 wt%
1334.4 ∠ 35. 2 1683.8 ∠ 33.32 2600.0 ∠ 41.2 260.0
Z100 288.9 ∠ 32. 2 937.4 ∠ 30. 0 2080.0 ∠ 40.1 208.0
Charisma 164.4 ∠ 52. 3 475.1 ∠ 54. 5 1449.3 ∠ 64.9 144.9
Clearfil 1006.9 ∠ 61. 9 1575.7 ∠ 62. 3 3881.7 ∠ 73.5 388.2
DenFil 1881.0 ∠ 34. 0 3585.5 ∠ 32. 3 6525.7 ∠ 37.1 652.6
Table 5.
Regression analysis of the complex viscosity of the experimental composites as a function of filler volume fraction. The exponential equation, y = aebx, was fitted to the data of Figure 3-b. Where y is the complex viscosity of composites and x is filler volume fraction.
Filler a b R statistic
0.7 um Ba 1.22 6.81 0.983
0.5 um Silica 1.33 8.18 0.997
0.04 um Silica 8.38 10.39 0.992
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      RHEOLOGICAL PROPERTIES OF RESIN COMPOSITES ACCORDING TO THE CHANGE OF MONOMER AND FILLER COMPOSITIONS
      J Korean Acad Conserv Dent. 2004;29(6):520-531.   Published online January 14, 2004
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    RHEOLOGICAL PROPERTIES OF RESIN COMPOSITES ACCORDING TO THE CHANGE OF MONOMER AND FILLER COMPOSITIONS
    Image Image Image Image Image Image Image Image Image Image Image Image Image
    Figure 1. Relationship between shear storage modulus (G′), shear loss modulus (G″), complex shear modulus (G*) and loss tangent (tanδ) in a complex plane.
    Figure 2-a. Viscosity of monomer blends of varying diluent’s concentration as a function of shear rates at 25℃.
    Figure 2-b. Steady shear viscosity, η, and dynamic complex viscosity, η*, of Bis-GMA only and Bis-GMA 6 : TEGDMA 4 blend at 25℃ and 35℃.
    Figure 2-c. Viscosity as a function of diluent fraction at temperature 25℃ and 35℃.
    Figure 3-a. Complex viscosity of experimental composites of varying filler contents (weight%) as a function of frequency.
    Figure 3-b. The effect of filler size and filler volume% on the complex viscosity of experimental composites at ω= 10 rad/s.
    Figure 3-c. Exponential regression curve, y = aebx, can be fitted on the complex viscosity of experimental composite with 0.5 um Silica as a function of filler volume fraction.
    Figure 4-a. The change of storage modulus G′and loss modulus G″with increasing filler content in 0.7um Ba glass.
    Figure 4-b. Loss tangent (Tanδ) of experimental composites as a function of filler volume %.
    Figure 5. Complex viscosity of experimental composites is exponentially decreased with increasing temperature.
    Figure 6. Complex viscosity of experimental and commercial composites as a function of frequency.
    Figure 7-a. Phasor representations of complex modulus G* and phase angle, δ, G*eiδ= G*∠δ, of experimental and commercial composites at ω= 10 rad/s in a polar coordinate system.
    Figure 7-b. Locus of frequency domain phasor plots, G*(ω )eiδ=G*(ω )∠δ, of composites at ω= 0.1 - 100 rad/s in a complex plane.
    RHEOLOGICAL PROPERTIES OF RESIN COMPOSITES ACCORDING TO THE CHANGE OF MONOMER AND FILLER COMPOSITIONS
    Monomers
      Bis-GMA 2,2-bis-[4-(methacryloxy-2-hydroxy-propoxy)-phenyl]-propane
    Manufacturer; Aldrichi, Germany
      TEGDMA Triethylene glycol dimethacrylate
    Manufacturer; Aldrichi, Germany
    Inorganic fillers
      Filler Type Abbreviation Manufacturer
      1) 0.7 um barium glass irregular 0.7 um Ba Schott, Germany
      2) 1.0 um barium glass irregular 1.0 um Ba Schott, Germany
      3) 40 ㎚ fumed silica (Aerosil OX-50) round 0.04 um Silica Degussa, Germany
      4) 0.5 um silica round 0.5 um Silica Youthtech, Korea
    Commercial Composite
      Z100 3M, USA
      Charisma Kulzer, Germany
      Clearfil Kuraray, Japan
      DenFil Vericom, Koreea
    (1) 0.7 um Ba
    50 (30.3), 60 (39.5), 70 (50.4), 75 (56.7) wt%
    (2) 1.0 um Ba
    60 (39.5), 75 (56.7) wt%
    (3) 0.04 um Silica
    30 (19.7), 40 (27.6), 50 (36.4), 55.9 (42.1) wt%
    (4) 0.5 um Silica
    30 (19.3), 35 (23.1), 40 (27.1), 45 (31.3) wt%
    (5) 0.7 um Ba 70 wt% + 0.04 um Silica 5 wt% - hybrid composite (57.2 vol%)
    (6) 0.7 um Ba 65 wt% + 0.04um Silica 10 wt% - hybrid composite (57.7 vol%)
    Monomer blends Shear viscosity (Pa.s)
    Bis-GMA vs. TEGDMA 25 ℃ 35 ℃
    Bis-GMA only 369 52.6
    8 : 2 5.04 1.46
    7 : 3 1.280 0.476
    6 : 4 0.429 0.203
    5 : 5 0.144 0.085
    4 : 6 0.066 0.021
    3 : 7 0.035 0.0213
    2 : 8 0.022 0.014
    TEGDMA only 0.0077 0.0068
    Composites G* (Pa) ∠ δ(°) η* (Pa.s)
    ω= 0.1 rad/s ω= 1 rad/s ω= 10 rad/s ω= 10 rad/s
    0.7 um Ba
      50 wt% 17.7 ∠ 55. 3 43.6 ∠ 58. 1 129.3 ∠ 72.3 12.9
      60 wt% 55.3 ∠ 43. 9 81.2 ∠ 53. 3 205.9∠ 69.5 20.6
      70 wt% 48.6 ∠ 39. 1 111.8 ∠ 48. 2 311.2 ∠ 67.1 31.1
      75 wt% 137.5 ∠ 40. 8 280.2 ∠ 44. 1 610.5 ∠ 61.1 61.1
    1 um Ba
      60 wt% 5.3 ∠ 50. 2 23.3 ∠ 60. 9 108.4 ∠ 74.9 10.8
      75 wt% 46.7 ∠ 42. 4 117.1 ∠ 50. 7 348.1 ∠ 69.0 34.8
    0.04 um Silica
      30 wt% 235.0 ∠ 53. 5 95.9 ∠ 62. 9 235.0 ∠ 71.7 23.5
      40 wt% 240.1 ∠ 61.34 768.2 ∠ 57. 9 1274.0 ∠ 65.1 127.4
      50 wt% 1792.8 ∠ 57. 4 2982.2 ∠ 48. 6 4179.0 ∠ 51.3 417.9
      55.9 wt% 6202.9 ∠ 42. 8 4710.4 ∠ 41. 8 6453.0 ∠ 43.7 645.3
    0.5 um Silica
      30 wt% 4.0 ∠ 71. 0 14.4 ∠ 79. 0 65.4 ∠ 83.2 6.5
      35 wt% 9.0 ∠ 68. 9 23.5 ∠ 75. 6 91.9 ∠ 82.3 9.2
      40 wt% 18.9 ∠ 66. 3 42.9 ∠ 71. 0 120.9 ∠ 81.5 12.1
      45 wt% 39.0 ∠ 63. 1 74.8 ∠ 65. 2 169.8 ∠ 77.7 17.0
    0.7 um Ba 70 wt% + 0.04 um Silica 5 wt%
    370.3 ∠ 40. 5 690.6 ∠ 39. 0 1299.5 ∠ 49.3 129.9
    0.7 um Ba 65 wt% + 0.04 um Silica 10 wt%
    1334.4 ∠ 35. 2 1683.8 ∠ 33.32 2600.0 ∠ 41.2 260.0
    Z100 288.9 ∠ 32. 2 937.4 ∠ 30. 0 2080.0 ∠ 40.1 208.0
    Charisma 164.4 ∠ 52. 3 475.1 ∠ 54. 5 1449.3 ∠ 64.9 144.9
    Clearfil 1006.9 ∠ 61. 9 1575.7 ∠ 62. 3 3881.7 ∠ 73.5 388.2
    DenFil 1881.0 ∠ 34. 0 3585.5 ∠ 32. 3 6525.7 ∠ 37.1 652.6
    Filler a b R statistic
    0.7 um Ba 1.22 6.81 0.983
    0.5 um Silica 1.33 8.18 0.997
    0.04 um Silica 8.38 10.39 0.992
    Table 1. Monomers and inorganic fillers used to make experimental composites and commercial composites.

    Table 2. The experimental composites were made with various types, size and weight% (the unit of the numbers in the parenthesis are volume%) of fillers added to resin matrix (Bis-GMA 6 : TEGDMA 4).

    Table 3. The shear viscosity of monomer blends at 25 ℃ and 35℃.

    Table 4. The phasor presentation of complex modulus G* and phase angle δ, G*(ω )eiδ=G*(ω )∠δ , and the complex viscosity η* of experimental and commercial composites at 25℃.

    Table 5. Regression analysis of the complex viscosity of the experimental composites as a function of filler volume fraction. The exponential equation, y = aebx, was fitted to the data of Figure 3-b. Where y is the complex viscosity of composites and x is filler volume fraction.


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