Study On The Blending Modification Of Phthalocyanine Resin And Its Composite Materials

As a new type of high-performance resin matrix,phthalocyanine resin(PN)has many advantages: Tg above 400 ?,excellent mechanical properties,excellent thermal stability at high temperature,and low water absorption.With its outstanding advantages,phthalocyanine resin has been widely used in the aerospace field.The above advantages of the phthalocyanine resin stem from the large rigid ring in the cured product after its own curing,such as a phthalocyanine ring.The phthalocyanine ring brings excellent performance and also causes the cured product to be brittle and rigid,so it needs to be added Other resins form a blended resin system to reduce the rigidity of the cured product of the phthalocyanine resin.In this paper,the principle of selecting the blending resin is to reduce the rigidity of the phthalocyanine resin to a certain extent on the basis of reducing the high heat resistance of the phthalocyanine resin,so this paper chose cyanate(CE)and polyether ketone(PEK)as the modified blending resin.When preparing the phthalocyanine resin composite material,it is considered that the carbon fiber surface and the phthalocyanine resin have poor wettability,and the prepared composite material is prone to interlayer damage,so the carbon fiber surface needs to be acidified.In this paper,the molecular simulation software Materials Studio was used to simulate the compatibility,Tg,elastic modulus and free volume fraction of the blended resin system,and the optimal mass fraction of cyanate ester and polyether ketone was determined.Before the simulation,the degree of polymerization of the polyetherketone in the simulation unit was determined,mainly considering the density,solubility parameters and calculation.After simulation,when the degree of polymerization is greater than or equal to 10,the density and solubility parameters of the polyetherketone unit cell tend to be stable.Consider In terms of computing power,polyetherketone with a degree of polymerization of 10 was used as the structure of this simulation.Cells were constructed using PN monomer,CE monomer and polyetherketone segment with a polymerization degree of 10,and the solubility parameters were calculated.The simulation results were: phthalocyanine monomer 21.17,cyanate monomer 21.06 and poly Ether ketone 20.95,the solubility parameters of cyanate ester,polyether ketone and phthalocyanine resin are all within 0.5,indicating that cyanate ester and polyether ketone are both thermodynamically compatible with phthalocyanine resin.The cyanate cured product,polyether ketone and phthalocyanine resin cured product were constructed into 5 wt%,10 wt%,15 wt% and 20 wt% blend unit cells and simulated F-H parameters,glass transition temperature and elasticity Modulus,simulation results show that all systems have good compatibility;as the CE and PEK content increases,the glass transition temperature of the blended resin system decreases;the elastic modulus of the 20 wt% cyanate blended resin system is the lowest It is 3.03 GPa;the minimum elastic modulus of the 10wt% polyetherketone blend resin system is 2.96 GPa.From the free volume fraction,it can be seen that the free volume fraction of 20 wt% cyanate ester and 10 wt% polyetherketone in the respective blended resin system reached the lowest value.Comprehensive consideration to determine the best added mass fraction of cyanate and polyetherketone is 20% and 10%.The cyanate ester and polyether ketone were blended with the phthalocyanine resin by melt blending method.The changes of the groups before and after the curing of the blended resin were studied by infrared spectroscopy.The results showed that the addition of CE and PEK did not give the phthalocyanine resin.Bring too much change.The test results of the rotary rheometer showed that the viscosity of the system did not change basically after the addition of CE and PEK.DSC results show that the addition of CE will increase the curing temperature of the system;the addition of PEK basically does not change the curing temperature of the system.TG results show that the addition of CE and PEK reduces the thermal stability of the system.The three-point bending results show that the modulus of the PN,20 wt%CE,and 10 wt%PEK systems are 4.01,3.19,and 2.58 GPa,respectively.The results show that the addition of CE and PEK effectively reduces the stiffness of the PN system.After acidification treatment,the degree of surface disorder,oxygen-containing functional groups and surface roughness of carbon fiber are increased to a certain extent.The interlaminar shearing results show that the modified carbon fiber has improved binding properties with the resin,and the ILSS has increased from 25 MPa to 34 MPa.Materials Studio software was used to simulate the binding energy of the carbon fiber before and after modification with the resin.The results showed that the binding energy of the carbon fiber after acidification treatment increased from 6609.85 kcal/mol to 12805.96 kcal/mol.