Skip to main content

Effect of curing order on the curing kinetics and morphology of bisGMA/DGEBA interpenetrating polymer networks

The full text article is not available for purchase.

The publisher only permits individual articles to be downloaded by subscribers.

The curing kinetics and morphology of an interpenetrating polymer network (IPN) formed from an epoxy resin (DGEBA) cured by an imidazole (1‐MeI) and a dimethacrylate resin (bisGMA), cured by low‐ and high‐temperature peroxide initiators (TBPEH and DHPB, respectively) have been studied by temperature‐ramping DSC, isothermal near‐infrared (NIR), DMTA and small‐angle neutron scattering (SANS). bisGMA and DGEBA are polar and chemically similar thermosetting resins which should enhance the miscibility of their IPNs. The phase structure was controlled by varying the curing procedure: the order of gelation of the components is dependent on the choice of low‐ and high‐temperature initiators for bisGMA and this affects the morphology formation. In the cure of the bisGMA/TBPEH:DGEBA/1‐MeI system, the dimethacrylate cures first. For isothermal cure studies at 80 °C, the final conversion of the epoxy is reduced by high crosslinking of the methacrylate groups in the IPN causing vitrification before full cure. The dimethacrylate conversion is enhanced due to plasticisation with unreacted DGEBA, and its cure rate is increased due to accelerated decomposition of TBPEH initiator by 1‐MeI. SANS revealed that phase separation occurs in these IPNs with domains on the scale of 6–7 nm. In the cure of the bisGMA/DHBP:DGEBA/1‐MeI system, the epoxy cures at a similar rate to that of the methacrylate groups. For isothermal cure studies at 80 °C, similar final conversions of the epoxy have been observed except for the 75:25 IPN. The cure rate of the methacrylate groups in the IPN is increased also due to accelerated decomposition of DHBP initiator by 1‐MeI, and the extent of accelerated decomposition for DHBP is stronger than that in the TBPEH‐based systems. SANS studies revealed that this system is more homogeneous due to the rapid formation of the dimethacrylate gel in the presence of the preformed epoxy network which interlocks the networks at low degrees of methacrylate conversion. Copyright © 2006 Society of Chemical Industry
No References
No Citations
No Supplementary Data
No Article Media
No Metrics

Keywords: IPNs; NIR; SANS; dimethacrylate; epoxy; kinetics; phase separation

Document Type: Research Article

Publication date: 2006-09-01

More about this publication?
  • Access Key
  • Free content
  • Partial Free content
  • New content
  • Open access content
  • Partial Open access content
  • Subscribed content
  • Partial Subscribed content
  • Free trial content
Cookie Policy
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more