Study On The Preparation And Performance Of Rosin-based Self-healing Materials

Given the self-repairing ability of polymer materials,it can improve the performance of the material and extend its service life,and at the same time can reduce the generation of plastic waste.Therefore,in recent years,self-repairing polymer materials have become a research hotspot.At present,most of the raw materials for preparing self-healing polymer materials are derived from petrochemical energy derivatives.When the materials are recycled for many times,it is inevitable that they will eventually become garbage and have to face the problem of disposal.If it is directly landfilled or incinerated,it will cause environmental pollution and endanger human health.Using biomass resources as raw materials to prepare polymer materials can reduce environmental pollution and reduce the dependence on petrochemical energy in the material preparation process.Therefore,this paper chooses forestry high-quality resource rosin as raw material,introduces dynamic chemical bonds after chemical modification to prepare rosin-based self-healing polymer materials,and uses the rigid tricyclic diphenanthrene structure of rosin to enhance the mechanical properties and thermal stability of the material.1.Diels-Alder（DA）reaction of rosin and maleic anhydride produces maleopimaric anhydride.The structure of maleopimaric anhydride.is characterized by Proton Nuclear Magnetic Resonance Spectroscopy（¹H NMR）,Carbon Nuclear Magnetic Resonance Spectroscopy(¹³C NMR)and Fourier Infrared Spectroscopy（FT-IR）.Synthesize maleepimaric acid polyester polyol（MAPP）by the reaction of maleepimaric acid anhydride and diethylene glycol,and react with isophorone diisocyanate（IPDI）and 1,6-hexamethylene diisocyanate（HDI）,respectively,by introducing heat Reversible DA reaction to obtain self-healing polyurethane materials（MAPP-IPDI and MAPP-HDI）.The results show that the glass transition temperature（Tg）of the two self-healing polyurethane materials is much higher than room temperature,and the Tg of MAPP-IPDI is as high as 60.3°C;MAPP-IPDI has excellent tensile strength and self-healing properties,and the tensile strength reaches 7.5 MPa.The repaired tensile strength after fracture reached 70%of the original sample;the tensile strength of MAPP-HDI was 5.1 MPa,the elongation at break was 112.5%,and the repaired tensile strength after fracture reached 86%of the original sample;self-repair Polyurethane materials（MAPP-IPDI and MAPP-HDI）have good bonding ability,and the tensile shear strength of MAPP-IPDI is as high as 2.4 MPa.2.In order to further improve the performance of rosin-based self-healing polyurethane,we use long-chain polytetrahydrofuran ether glycol to replace part of malepimaric acid polyester polyol to prepare self-healing polyurethane（MAPP-x,x stands for malepimaric acid polyol）.The ratio of ester polyol to alcohol,the same below).Investigating the effect of rosin polyester polyol content on polyurethane performance,the study found that as the content of rosin polyester polyol increases,the thermal stability of polyurethane first increases and then decreases.The temperature of T-5%corresponding to MAPP-x is higher than 230 ^oC;the elongation at break of MAPP-x decreases with the increase of rosin polyester polyol content,the elongation at break of MAPP-IPDI_0.25is as high as 339.5%,and the elongation at break of MAPP-IPDI_0.75is only 2.7%;With the increase of polyester polyol content,the tensile strength of MAPP-HDI series modified polyurethane has increased from 2.1 MPa of MAPP-HDI_0.25to7.0 MPa of MAPP-HDI_0.75,an increase of more than 3 times;MAPP-IPDI The tensile strength of the modified polyurethane series first increases and then decreases with the increase of the rosin polyester polyol content.The tensile strength of MAPP-IPDI _0.50is the highest,reaching19.7 MPa;with the rosin polyester polyol content With the increase of,the self-repair efficiency of polyurethane decreases,and the self-repair efficiency of MAPP-HDI_0.25is the highest,which can reach 90%.The shear strength of MAPP-IPDI_0.50is as high as 4.9 MPa,which can be used as an adhesive.3.In order to minimize the use of fossil resources,the rosin derivative propylene pimaric acid and epoxy soybean oil are used as raw materials,and zinc acetylacetonate is used as a catalyst to cure to obtain a fully bio-based self-healing material（APA-ESO-y,y represent the ratio of the amount of carboxyl group and epoxy group substance,the same below）.Studies have shown that as the content of acrylpimaric acid increases,the thermal stability and Tg of the material are improved,that is,the T-5%of APA-ESO_1.25is as high as 293°C,and the Tg of APA-ESO_1.25is as high as 85.4°C.The self-healing material has excellent mechanical properties.The tensile strength of APA-ESO_1.00can reach 18.82 MPa,and it shows excellent self-healing performance and reprocessing performance.Scratch self-repair test shows that:the repair temperature is 180°C,the repair time is 5 minutes,and the repair efficiency of APA-ESO_0.75can reach 90.3%;the repair time is 30 minutes,and the repair efficiency can reach 92.9%.In addition,APA-ESO_1.00can be reprocessed by ethanol dissolution and hot pressing,and the tensile strength of the reprocessed sample can reach 89%of the original sample.