Synthesis Of Poly-(1,2,3-triazole) Resin Containing Phthalazinone And Its Modified Monomer Casting Polyamide 6

As known, monomer casting polyamide 6 (MCPA6) has poor toughness and dimensional stability in dry and low temperature. Herein, started from the design of molecular structure, a series of poly-(1,2,3-triazole) thermoplastic resin (m-DBDs) having twisted non-coplanar phthalazinone structure in the polymer backbone were designed and then synthesized by "click chemistry" solution polymerization reaction through azide and alkyne reaction. Then the modification of MCPA6 was carried out by the kind of the resulting poly-(1,2,3-triazole).Three monomers, including 1,3-bis (propargyl oxy) benzene (m-BPOB),4-[4-(propargyl oxy) phenyl]-2-(propargyl oxygen) phthalazin-1-one (DHPZ-d) and 4-4' diazide methyl biphenyl (DAMBP) were firstly designed and synthesized. Subsequently a series of poly-(1,2,3-triazole) (m-DBD) containing phthalazinone moiety were synthesized by the solution polymerization of m-BPOB, DHPZ-d and DAMBP. Their structure and properties were characterized. The results show that the glass transition temperature of the resulting polymers are significantly increased with the increase of mole ratio of DHPZ-d, from 164? to 197?. Their decomposition temperatures for 5% mass-loss are around 360?. The tensile strength of the polymer film are between 68?75 MPa with 13.8-16.5% of the elongation at break.DBD-d/MCPA6 in situ polymerization composites were prepared. The mass fraction of DBD-d which had the best heat resistant performance were 0%,2%,4%,6% and 8%. The kinetics of isothermal and non isothermal crystallization kinetics in this system were investigated by DSC. The results show that the crystallization rate and the parameter values of K are higher and the parameter values of the half-time for crystallization (t1/2) is lower when adding a certain amount of DBD-d, indicating that DBD-d has the role of heterogeneous nucleation. The activation energy of the isothermal crystallization and non isothermal crystallization of DBD-d/MCPA6 composites increase firstly and then decrease with the increase of DBD-d content.The properties of MCPA6 and DBD-d/MCPA6 in situ composites were studied. The results show that the glass transition temperatures of the composites are higher than 75?, while the temperatures of the 95% retention of weight are between 290?296?.When the content of DBD-d is less, the tensile strength of the composites is very small compared with that of pure MCPA6. Their elongation at break increase and the flexural strength decrease with the increase of DBD-d content. The notched impact strength reaches 5.46 KJ/m2,21% higher than that of pure MCPA6. Notched impact fracture were observed by SEM. It has been found that the section of the composites is relatively rough, but its degree of roughness increase firstly and then decrease with the increase of DBD-d content. Meanwhile, a large number of micro holes were found on the etched surface, indicating that the polymer DBD-d and the matrix MCPA6 are two-phase structure.