Analysis of a dimethacrylate copolymer (Bis-GMA and TEGDMA) network by DSC and 13C solution and solid-state NMR spectroscopy

Morgan, D. R.; Kalachandra, S.; Shobha, H. K.; Gunduz, Nazan; Stejskal, E. O.

doi:10.1016/s0142-9612(00)00067-3

Cited by 67 publications

(47 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In general, dental composites reach a DC% ranging from 43 to 75%, basically depending on the composite composition, PD, and exposure time [49,51,53,56,57]. The DC% values in this study varied from 48.77% (±2.76) to 54.46% (±2.39) which also agrees with the DC% observed in other studies [6,9,30].…”

Section: Resultssupporting

confidence: 89%

See 1 more Smart Citation

Continuous and gradual photo-activation methods: influence on degree of conversion and crosslink density of composite resins

Costa

Galvão

Jacomassi

et al. 2010

J Therm Anal Calorim

View full text Add to dashboard Cite

Thermal properties and degree of conversion (DC%) of two composite resins (microhybrid and nanocomposite) and two photo-activation methods (continuous and gradual) displayed by the light-emitting diode (LED) light-curing units (LCUs) were investigated in this study. Differential scanning calorimetry (DSC) thermal analysis technique was used to investigate the glass transition temperature (T g ) and degradation temperature. The DC% was determined by Fourier transform infrared spectroscopy (FT-IR). The results showed that the microhybrid composite resin presented the highest T g and degradation temperature values, i.e., the best thermal stability. Gradual photo-activation methods showed higher or similar T g and degradation temperature values when compared to continuous method. The Elipar Freelight 2 TM LCU showed the lowest T g values. With respect to the DC%, the photoactivation method did not influence the final conversion of composite resins. However, Elipar Freelight 2 TM LCU and microhybrid resin showed the lowest DC% values. Thus, the presented results suggest that gradual method photoactivation with LED LCUs provides adequate degree of conversion without promoting changes in the polymer chain of composite resins. However, the thermal properties and final conversion of composite resins can be influenced by the kind of composite resin and LCU.

show abstract

Section: Resultssupporting

confidence: 89%

“…Techniques such as FT-IR [47,48], RAMAN spectroscopy [42,49], electron paramagnetic resonance (EPR) [50], nuclear magnetic resonance (NMR) [51], DSC [52] and differential thermal analysis (DTA) [53] have been used to determine the DC%. Among these, FT-IR is the most frequently used technique [46].…”

Section: Resultsmentioning

confidence: 99%

Continuous and gradual photo-activation methods: influence on degree of conversion and crosslink density of composite resins

Costa

Galvão

Jacomassi

et al. 2010

J Therm Anal Calorim

View full text Add to dashboard Cite

show abstract

“…) and wet (after 1 mo, 3 mo and 6 mo immersion in HEPES-buffered saline solution (0.13 mol/L NaCl; pH = 7.4) at 23 °C; 40 mL saline solution/specimen) copolymer and composite specimens (a minimum of 7 specimens per group) were calculated according to the following equation [13]: (1) where 2 ], and where ν = Poisson's ratio, r l = radius of the piston applying the load at the surface of contact, r sc = radius of the support circle, r s = radius of disk specimen, L = applied load at failure, and t = thickness of disk specimen. A constant value of 0.24 was used for Poisson's ratio, in accordance with published data on the elastic properties of resin-based composites [14].…”

Section: Physicochemical Testing Of Copolymers and Compositesmentioning

confidence: 99%

“…Methacrylate polymeric networks with good resistance to aqueous milieu are sought for use in both prophylactic and restorative dentistry [1]. The most commonly utilized binary dental resins contain 2,2-bis[p-(2'-hydroxy-3'-methacryloxypropoxy)phenyl]propane (Bis-GMA; a highly viscous base monomer) and tri(ethylene glycol) dimethacrylate (TEGDMA; a fluid, flexible diluent monomer).…”

Section: Introductionmentioning

confidence: 99%

Light-Cured Dimethacrylate-Based Resins and Their Composites: Comparative Study of Mechanical Strength, Water Sorption, and Ion Release

O'Donnell

Langhorst

Fow

et al. 2008

Journal of Bioactive and Compatible Polymers

View full text Add to dashboard Cite

This study explored how resin type affects selected physicochemical properties of complex methacrylate copolymers and their amorphous calcium phosphate (ACP)-filled and glass-filled composites. Two series of photo-polymerizable resin matrices were formulated employing 2,2-bis [p-(2'-hydroxy-3'-methacryloxypropoxy)phenyl]propane (Bis-GMA) or an ethoxylated bisphenol A dimethacrylate (EBPADMA) as the base monomer, Unfilled copolymers and composites filled with a mass fraction with 40 %, 35 % and 30 %, respectively, of ACP or the un-silanized glass were assessed for biaxial flexure strength (BFS), water sorption (WS) and mineral ion release upon immersion in HEPES-buffered saline solution for up to six months. Substituting EBPADMA for Bis-GMA significantly reduced the WS while only marginally affected the BFS of both dry and wet copolymers. Independent of the filler level, both dry and wet ACP composites formulated with either BTHM or ETHM resins were mechanically weaker than the corresponding copolymers. The BFS of ACP composite specimens after 1 month in saline did not further decrease with further aqueous exposure. The BFS of glass-filled composites decreased with the increased level of the glass filler and the time of aqueous exposure. After 6 months of immersion, the BFS of glass-filled BTHM and ETHM composites, respectively, remained 58 % and 41 % higher than the BFS of the corresponding ACP composites. Ion release data indicated that a minimum mass fraction of 35 % ACP was required to attain the desired solution supersaturation with respect to hydroxyapatite for both the BTHM and ETHM derived composites.

show abstract

“…Moreover, the trend in the final double-bond conversion and conversion at R p max is the same as that reported in the literature. 11,12,[24][25][26][27][28] The differences observed between our data and the corresponding literature data could be attributed to a number of reasons, including the different initiation systems used (redox in our study vs photopolymerization in some cases 11,12 ), a higher reaction temperature (378C in our study vs 28 11 or 258C 12 ), longer reaction times (until 60 min for TEGDMA in our study vs 10-15 min in the literature 11 ), larger sample masses in DSC (15-20 mg in this study vs 1-4 mg 11 ), and different monomer suppliers. Thus, it seems that the results presented here could be considered unique for the particular conditions employed.…”

Section: Copolymerization Kineticsmentioning

confidence: 99%

Copolymerization kinetics of dental dimethacrylate resins initiated by a benzoyl peroxide/amine redox system

Sideridou

Achilias

Kostidou

2008

J of Applied Polymer Sci

View full text Add to dashboard Cite

The copolymerization of four dental dimethacrylates initiated by a benzoyl peroxide/4-N,N-dimethylamino phenethyl alcohol redox system at 378C was studied with differential scanning calorimetry. The studied dimethacrylates were viscous bisphenol A glycidyl dimethacrylate (Bis-GMA), bisphenol A ethoxylated dimethacrylate (Bis-EMA), and urethane dimethacrylate (UDMA), which were characterized as base monomers, and low-viscosity triethylene glycol dimethacrylate (TEGDMA), which was characterized as a diluent. Also, three series of dimethacrylate copolymers were prepared by incremental additions (12.5 wt %) of TEGDMA to a base comonomer (Bis-GMA, UDMA or Bis-EMA). The maximum rate of homopolymerization of the dimethacrylates followed the order of Bis-GMA > UDMA > TEGDMA > Bis-EMA, and the final degree of conversion of the corresponding homopolymers followed the order of TEGDMA > UDMA > Bis-EMA > Bis-GMA. A reaction-diffusion-controlled termination region was clear in all monomers and started earlier in bulky and rigid Bis-GMA and Bis-EMA (followed by the more flexible UDMA and TEGDMA) but lasted longer in the Bis-EMA polymerization. The maximum rate of copolymerization and degree of conversion of copolymers of a base monomer with TEGDMA changed monotonically with an increase in the TEGDMA content in the initial comonomer mixture. A synergistic effect was clear only in the final double-bond conversion of Bis-GMA/TEGDMA.

show abstract

Analysis of a dimethacrylate copolymer (Bis-GMA and TEGDMA) network by DSC and 13C solution and solid-state NMR spectroscopy

Cited by 67 publications

References 17 publications

Continuous and gradual photo-activation methods: influence on degree of conversion and crosslink density of composite resins

Continuous and gradual photo-activation methods: influence on degree of conversion and crosslink density of composite resins

Light-Cured Dimethacrylate-Based Resins and Their Composites: Comparative Study of Mechanical Strength, Water Sorption, and Ion Release

Copolymerization kinetics of dental dimethacrylate resins initiated by a benzoyl peroxide/amine redox system

Contact Info

Product

Resources

About