Preparation Of Polar Functionalized Polyethylene Based On Palladium Catalyst

Polyolefin materials are widely used because of their excellent properties,but their non-polar properties limit their development prospects and application fields.The introduction of polar functional groups into polyolefins can greatly change the properties of polyolefins,give polyolefin materials more performance,and greatly expand the application fields of polyolefin materials.The late transition metal catalyst palladium phosphine sulfonate(PO-Pd)has outstanding performance in catalyzing the copolymerization of ethylene and polar monomers,and has universality for the preparation of polar polyolefin materials by catalytic copolymerization.In this paper,the preparation of polar functionalized polyethylene materials based on PO-Pd catalysts and the effects of different monomer concentrations and different polar groups on their performance are studied.Mainly include the following aspects of work:1.The PO-Pd catalyst was successfully prepared and characterized.And under different concentration conditions,using PO-Pd as a catalyst,the binary copolymerization of ethylene and diene norbornene monomers and the ternary copolymerization of norbornene monomers containing different polar functional groups were carried out.The results show that while achieving high polymerization activity and high molecular weight,the polar monomer insertion rate is higher than 2%,up to 12.5%,and the proportion of polar monomers in the copolymer can be adjusted within a larger range.2.By analyzing and comparing the tensile properties,elastic properties,wetting properties,dyeing properties,adhesive properties,blending properties and adsorption properties of the prepared copolymers,it is found that most of these copolymers exhibit elastomeric properties at room temperature.The insertion of polar monomers can significantly change the properties of the material.The specific performance is:the tensile strength of the E-DCPD1.0-NB^COOH0.5 terpolymer is as high as 50.6 MPa,the elongation at break is 735%,and the water contact angle is the lowest.Down to 65°;dyeing performance and dyeing stability are significantly improved;adhesive tensile strength can reach up to 9MPa;blending performance studies show that polyethylene materials with polar groups are a good compatibilizer and toughening for non-polar polyolefin materials Agent.3.The diene-type norbornene monomer has unsaturated double bonds,which provide active sites for the further processing of the copolymer.In this paper,sulfur-containing commercial formulations were used to carry out vulcanization studies on selected terpolymers.Through analysis and comparison of their tensile properties and elastic properties,it was found that the cross-linked network constructed by vulcanization cross-linking increased the tensile strength of the copolymer 2-4 times without affecting its elastic properties.