Study On The Relationship Between Hard Segment Of Polyurethane Microstructure And Vibration Transfer Properties

Polyurethane Elastomer is a multi block polymer,and its excellent low temperature resistance,abrasion resistance,high bearing capacity and high toughness make it widely used throughout the world.And the types and proportions of raw materials of each component can be adjusted.Therefore,different formulations of polyurethane elastomers can be made according to actual use environment needs.In addition,polyurethane elastomers have special micro-phase separation structure because of their special internal micro-phase separation structure,which has shown special performance,and has attracted the interest of many researchers in terms of damping and vibration isolation.There has been a large amount of literature reporting that polyurethane elastomers have higher damping,lower natural frequencies,and better vibration isolation effects than conventional rubber materials,and the performance analysis of their vibration isolation is limited to software simulations.However,few literatures describe in detail the internal structure of polyurethane elastomers,especially the relationship between hard segment structures and vibration isolation characteristics that have great influence on their properties.This article starts with the structure of the hard segment,design a series of polyurethane elastomers with different formulations,and use independent building vibration isolation equipment to explore and analyze the relationship between its structure and vibration isolation performance.Specifically,it will be divided into the following sections to discuss:Firstly,the effect of diisocyanate on the vibration isolation of polyurethane elastomers was investigated.According to the different factors,it is divided into two types of diisocyanate and the symmetry of diisocyanate.In the design of different types of formulations,we chose two isocyanates containing aliphatic isocyanate and aromatic isocyanate,namely HMDI and MDI,respectively,and PPG-2000 synthetic prepolymer,and use the same chain extender.After the preparation of the cross-linking agent,the experimental analysis was performed.In the second part,two isocyanate TDI-80 and TDI-100 containing different symmetry were selected to synthesize the corresponding polyurethane elastomer,and the isolating properties and other properties of the material were compared with the isocyanate symmetry.Secondly,the effect of the chain extender on its performance was explored,which was divided into the main chain length of the chain extender and the number of side groups of the chain extender and the parity of the carbon atom number of the chain extender.EG,BDO and HDO were selected as the research variables for the chain lengths of different chain extenders;the influence of the number of chain extender side chains on the material properties was studied.The number of three side groups of PDO,MPO and MPO was 0,1,2,respectively.Three kinds of chain extenders were prepared and compared respectively;EG and PDO were selected as chain extenders for small molecules,and raw materials with different parity were used for the preparation of polyurethane elastomer materials,and the relationship between structure and performance was investigated.Finally,the type of cross-linking agent,the cross-link density,the micro-properties of the polyurethane elastomer and the macro-isolation performance were investigated.Three commonly used crosslinkers with different structure,TEA,HTO,and GLY,were selected as variables;and TEA alone was chosen as a cross-linker to study the proportion of crosslinker,ie,the effect of crosslink density on the properties of the material.