The FTIR spectra of urethane dimethacrylate oligomers (e.
Returning to the low-molecular-weight urethane dimethacrylate (UAc-M) used together with bisGMA (1.
n]: 1000 g/mol) in the structure of urethane dimethacrylate included in the formulation of S1 composite produced photocured resins with relatively low contact angle (40.
15%) in the absence of filler may be correlated with the literature data, taking into account the fact that each urethane dimethacrylate is included in the polymeric specimen in a small amount (18 wt%).
Table 2 shows the results obtained by the mechanical evaluation of the Sl-S3 composites containing the aforementioned urethane dimethacrylate oligomers UMO-1, UMO-2, or UAc-M.
5, in the case of UAc-M/bisGMA (1:1) used in formulation, the influence of urethane dimethacrylate structure on the [I.
Compared with UMO-1, for the polymerization of low-molecular-weight urethane dimethacrylate (74.
3]MA), and urethane dimethacrylates with an aliphatic (UDMA) or partially aromatic (TMX-UDMA) core structure (4-6).
Two urethane dimethacrylates of oligomer type were prepared according to the general synthetic route shown in Scheme 1, via condensation of the poly(ethylene glycol) (PEG) with an aliphatic diisocyanate, such as IPDI, to yield a prepolymer with end isocyanate groups, which finally was converted to a dimethacrylate by the reaction with 2-hydroxyethyl methacrylate.
Kinetics of the free-radical polymerization of urethane dimethacrylates initiated with BP/PD was first investigated comparatively to a system based on a combination of CQ and tertiary amine (DMAEA), at ambient temperature.
For monitoring the photopolymerization of urethane dimethacrylates by fluorescence spectroscopy, 4-chloromethylphenylcarbamoyl-1-oxymethylpyrene was chosen as a spectroscopic probe and potential photosensitizer (29) that can provide information about the rigidity of the dental matrix in which this was inserted.