Diglycidyl-4,5-epoxycyclohexane-1,2-dicarboxylate(TDE-85)/methyl tetrahydrophthalic anhydride (MeTHPA) epoxy resin was modified with polyurethane(PU) and the interpenetrating polymer networks(IPNs) of PU-modified TDE-...Diglycidyl-4,5-epoxycyclohexane-1,2-dicarboxylate(TDE-85)/methyl tetrahydrophthalic anhydride (MeTHPA) epoxy resin was modified with polyurethane(PU) and the interpenetrating polymer networks(IPNs) of PU-modified TDE-85/MeTHPA resin were prepared. The structural characteristics and properties of PU-modified TDE-85/MeTHPA resin were investigated by Fourier transform infrared(FTIR) spectrum,emission scanning electron microscopy(SEM) and thermogravimetry(TG). The results indicate that epoxy polymer network (Ⅰ) and polyurethane polymer network (Ⅱ) of the modified resin can be obtained and the networks (Ⅰ) and (Ⅱ) interpenetrate and tangle highly each other at the phase interface. The micro morphology presents heterogeneous structure. The integrative properties of PU-modified TDE-85/MeTHPA epoxy resin are improved obviously. The PU-modified TDE-85/ MeTHPA resin's tensile strength reaches 69.39 MPa,the impact strength reaches 23.56 kJ/m,the temperature for the system to lose 1% mass (t1%) is 300 ℃,and that for the system to lose 50% mass (t50%) is 378 ℃. Compared with those of TDE-85/MeTHPA resin,the tensile strength,impact strength,t1% and t50% of the PU-modified resin increases by 48%,115%,30 ℃,11 ℃,respectively. The PU-modified TDE-85/MeTHPA resin has the structure characteristics and properties of interpenetrating polymer networks.展开更多
BaTiO3/ Interpenetrating Polymer Networks (IPNs) composites were prepared by combination of BaTiO3 nanocrystal in tetragonal system and polyurethane(PU)/ unsaturated polyester (UP) interpenetrating polymer networks (I...BaTiO3/ Interpenetrating Polymer Networks (IPNs) composites were prepared by combination of BaTiO3 nanocrystal in tetragonal system and polyurethane(PU)/ unsaturated polyester (UP) interpenetrating polymer networks (IPNs). The tetra gonal nanocrystalline BaTiO3 was obtained by hydrothermal process and calcinatio n at 1 200 ℃. The prepared materials were polarized with high voltage a nd small current, and protected by silicon oil. The morphology of BaTiO3/ IPNs and the effect of combination of BaTiO3 on the damping behavior of IPNs were stu died. The relationship between damping performance and dielectric charater was a lso discussed in terms of dielectric constant and dielectric loss measured. The results show that the areas under loss modulus (E″) and the values of loss fact ors (tanBaTiO3 into IPNs system. The m aximum value of E″ increased above 100 MPa compared with pure IPNs and the exte nt increased more remarkably after polarizing process. The main and shoulder pea k of tand the temperatu re ranges of tan℃. Moreover, through polarizing proc ess, the composites exhibited synergistic action caused by elastomeric damping, interfacial abrasive damping and piezoelectric damping mechanisms. The relations hip study of damping property and dielectric characters showed that the temperat ure ranges exhibited excellent consistency of maximum dielectric loss and modulu s with damping loss factor.展开更多
基金Project(2003AA84ts04) supported by the National High-Tech Research and Development Program of China
文摘Diglycidyl-4,5-epoxycyclohexane-1,2-dicarboxylate(TDE-85)/methyl tetrahydrophthalic anhydride (MeTHPA) epoxy resin was modified with polyurethane(PU) and the interpenetrating polymer networks(IPNs) of PU-modified TDE-85/MeTHPA resin were prepared. The structural characteristics and properties of PU-modified TDE-85/MeTHPA resin were investigated by Fourier transform infrared(FTIR) spectrum,emission scanning electron microscopy(SEM) and thermogravimetry(TG). The results indicate that epoxy polymer network (Ⅰ) and polyurethane polymer network (Ⅱ) of the modified resin can be obtained and the networks (Ⅰ) and (Ⅱ) interpenetrate and tangle highly each other at the phase interface. The micro morphology presents heterogeneous structure. The integrative properties of PU-modified TDE-85/MeTHPA epoxy resin are improved obviously. The PU-modified TDE-85/ MeTHPA resin's tensile strength reaches 69.39 MPa,the impact strength reaches 23.56 kJ/m,the temperature for the system to lose 1% mass (t1%) is 300 ℃,and that for the system to lose 50% mass (t50%) is 378 ℃. Compared with those of TDE-85/MeTHPA resin,the tensile strength,impact strength,t1% and t50% of the PU-modified resin increases by 48%,115%,30 ℃,11 ℃,respectively. The PU-modified TDE-85/MeTHPA resin has the structure characteristics and properties of interpenetrating polymer networks.
文摘BaTiO3/ Interpenetrating Polymer Networks (IPNs) composites were prepared by combination of BaTiO3 nanocrystal in tetragonal system and polyurethane(PU)/ unsaturated polyester (UP) interpenetrating polymer networks (IPNs). The tetra gonal nanocrystalline BaTiO3 was obtained by hydrothermal process and calcinatio n at 1 200 ℃. The prepared materials were polarized with high voltage a nd small current, and protected by silicon oil. The morphology of BaTiO3/ IPNs and the effect of combination of BaTiO3 on the damping behavior of IPNs were stu died. The relationship between damping performance and dielectric charater was a lso discussed in terms of dielectric constant and dielectric loss measured. The results show that the areas under loss modulus (E″) and the values of loss fact ors (tanBaTiO3 into IPNs system. The m aximum value of E″ increased above 100 MPa compared with pure IPNs and the exte nt increased more remarkably after polarizing process. The main and shoulder pea k of tand the temperatu re ranges of tan℃. Moreover, through polarizing proc ess, the composites exhibited synergistic action caused by elastomeric damping, interfacial abrasive damping and piezoelectric damping mechanisms. The relations hip study of damping property and dielectric characters showed that the temperat ure ranges exhibited excellent consistency of maximum dielectric loss and modulu s with damping loss factor.
