Abstract
AbstractThe development of internal stress during cure of epoxy and hyperbranched polymer‐modified epoxy resins was characterized, taking into account the evolving viscoelastic properties, the volumetric shrinkage due to the chemical reaction, and the thermal expansion. A criterion for void formation during cure in a constrained mold was proposed, providing guidelines for the construction of a process window for manufacturing of void‐free composites. It was shown that the internal stress development in epoxy resins during cure is strongly influenced by the presence of hyperbranched polymer modifiers. The role of these modifiers was illustrated for the case of autoclave processing of glass fiber/epoxy composites. This study showed that higher fiber volume fractions could be used with hyperbranched polymer‐modified resins than with unmodified resins, for producing void‐free laminates. It also appeared that by suitable tailoring of the process cycle, a fully stress‐free laminate could be obtained after cure, using the modified resin.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
