Preparation And Application Of Rosin-based Acrylamide Monomer

As the main component of disproportionated rosin,dehydroabietic acid has a carboxyl group in its structure,which could react with different chemical substances to obtain multifunctional polymerizable rosin monomer.Then the novel polymers could be gained by polymerization.As a kind of bio-based products,acrylated epoxidized soybean oil（AESO）with little irritation and low viscosity has been used in the coatings,packaging materials,paint,adhesives and other applications.However,because of its low glass transition temperature and poor mechanical properties and weak rigidity,they are restricted in some application fields.By introduction of polymerizable rosin monomer into AESO,the rigid structure of rosin may increase the glass transition temperature,thermal stability,mechanical properties and hydrophobicity of AESO.The polymerizable rosin monomers including N-dehydroabietic acrylamide（DHA-AM）and N-dehydroabietic ethoxycarbonyl acrylamide（DHA-HEMAA）were synthesized from disproportionated rosin as raw materials.And the purities of DHA-AM and DHA-HEMAA were 97.95%and 96.05%,respectively.The structure and performance of monomers were characterized by FT-IR,MS,¹H NMR,¹³C NMR.The characterization results showed that DHA-AM and DHA-HEMAA were all synthesized successfully.DSC analysis indicated that the thermal polymerization of DHA-AM was occurred during 151-196℃.Meanwhile,the thermal polymerization of DHA-HEMAA was occurred during 98-131 ℃.Non-isothermal DSC method was used to study the two types of polymerizable rosin-based acrylamide monomer reaction kinetics of bulk polymerization.And we dicussed and chose the model which could be used to simulate the process.The bulk polymerization reaction rates of DHA-AM and DHA-HEMAA all increased firstly and then decreased with increasing temperature.n-order reaction kinetic model put up great distinction to describe the bulk polymerization reaction of DHA-AM and DHA-HEMAA.Using Malek’s mechanism function method to analyze the experimental data,the two kinds of polymerizable rosin based acrylamide monomers have a tendency toward that 0<aM<aα_p^∞,and α_p^∞≠0.632.This can be described by the model of SB（m,n）in Malek’s mechanism function method.The calculated curves have little distinction with the experimental curves,so SB（m,n）model can simulate the two types of polymerizable rosin-based acrylamide monomer reaction kinetics of bulk polymerization well.This research not only provides a basis for the application of polymer in polymer material,but also expands the application fields of natural rosin resources.The DHA-AM and DHA-HEMAA were all introduced into an AESO/rosin-based acrylamide polymerizable monomer system to afford thermosetting resin by thermocuring,respectively.The structure and performance of the resulting thermosets were characterized by Fourier transform infrared（FT-IR）,Dynamic mechanical analysis（DMA）,Elemental analysis,Thermogravimetric analysis（TGA）and Contact angle analysis.The analyses manifested that:AESO/DHA-AM40 and AESO/DHA-HEMAA40 showed the first-rank mechanical property and hydrophobic property in all the cured samples.The tensile strength of AESO/DHA-AM40 and AESO/DHA-HEMAA40 reached 5.7 MPa and 6.5 MPa,respectively.The elongation at break of AESO/DHA-AM40 and AESO/DHA-HEMAA40 were 36.1%and 45.8%.With increasing the content of rosin-based acrylamide polymeric monomer introduced in the copolymer,the cured samples obtained the strongest hydrophobicity with the contact angle of 105° and 101°.The presences of DHA-AM and DHA-HEMAA moieties in the composite structures could expand the utilization of AESO to make its development toward heat-resisting and hydrophobic materials.