By the result knowable add a few MeMA solidify agent (the <20%) flexural strength impact to condensate is not big, but when the quality mark that should mix the MeMA in acid anhydride exceeds 20% , the flexural strength of condensate drops apparently. Achieve when the quality mark of the MeMA in mixture acid anhydride 40% when, flexural strength value fell 10% , should achieve 60% when, flexural strength dropped 20% . Because should give sample to bring to bear on bear, when sample suffers force happening deformation, of sample above it is to compress deformation, stretchy deformation is below, destroy majority to happen below first. Be less than the intensity of MeTHPA and the key that epoxy resin combines as a result of the intensity of MeMA and the key that epoxy resin combines, and MeMA and epoxy resin condensate have flexible, should add a few when MeMA solidify agent, the influence with abate intensity is offsetted by amortize stress place, flexural strength change is very little. Join MeMA when excessive, the influence with key abate intensity exceeded the impact of its amortize stress, bring about flexural strength to be reduced apparently.
(Impact strength analyses 3)
The recipe of condensate is the same as tensile strength, determine to see a table as a result 4.
Express 4 different the acid anhydride of epoxy resin 618/ that deserves to compare
MeTHPA is in the quality mark in solidify agent / % average impact strength / (KJ · M^{- 2}) draw energy on average / J 100 12 1.9 90 13 2.0 80 13 2.0 60 16 2.4 40 15 2.3
The impact strength of solidify system changes. Impact strength is to measure high polymer material to be touched in high speed attack next regarding <> as tough or fight the measurement that rupture, its token the ability that material resists concussion load is destroyed. By the watch knowable, when solidify reacts, when the quantity of the MeMA in mixture acid anhydride increases, the impact strength of condensate is shown increase a current, this is decided by the molecular structure of MeMA. There is long adipose chain in MeMA element, this are adipose catenary does not react with epoxy resin happening, and this catenary is linear element, make material can produce chain below fixed negative charge paragraph motion, make its are participated in consequently bear the catenary of outside force paragraph number increases, participate in namely absorb concussion can bulk increases, so impact strength increases. But when the amount with increase certain when MeMA, the impact strength of condensate is reduced somewhat again, the intensity that this is the key that is united in wedlock because of MeMA and epoxy resin is inferior to the intensity of MeTHPA and the key that epoxy resin combines, increase certain amount when MeMA (> after 40%) , the influence with abate intensity of the key inside sample exceeds the effect that increase because of participating in those who absorb impact strength bulk and produces, have dominant effect to impact strength, so impact strength drops somewhat again. (Article origin is round-the-world polyurethane net)
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