Preparation And Performance Of Functional Polypyrrole/Polyurethane Porous Materials

Porous polymers and their composite materials have multiple advantages of porous structure,polymer materials and modified components,therefore,it's of great significance to extend the application of functional porous polymer materials.And it's also the research trend of new multifunctional porous polymer materials.At present,although the research of functional porous polymer composite materials has made great progress,due to the limitation in material selection,porous preparation methods,material modification,etc.,many studies cannot fully utilize the advantages of porous polymer materials.In addition,issues such as cost,preparation technology,durability,etc.must also be considered in practical applications,as a result,some porous polymer composite materials with specific functions are limited to small-scale research in the laboratory and difficult to promote and apply in daily life and national production.Based on these reasons,in order to explore the possibility of porous polymer materials in practical applications,this paper optimizes and expands functional porous polymer materials in three aspects:preparation methods,functional modification and application research of porous polymer materials.The porous polyurethane material was prepared with polyurethane elastomer as the matrix by solution casting/template leaching method,where the leaching template was a solid model made of soluble sugar cubes or sugar particles.Then,the porous polyurethane material with an inverse template matrix structure was prepared through impregnation,suction filtration,curing and ultrasonic treatment processes.Taking the advantage of pyrrole easy to oxidative polymerization,the Fe Cl₃ solution was selected as the oxidant,the polypyrrole/polyurethane porous composite material was obtained by in-situ steam polymerization of pyrrole on the pore surface of the porous polyurethane.Through the swelling of pyrrole on the polyurethane elastic material,a microfolded structure was constructed on the surface of the porous pores to form a layered structure feature combining macroscopic macropores and microfolds on the surface of the pores,and then applied to sensing research.The sensing detection mechanism of polypyrrole/polyurethane sponge sensor was explored by characterizing the stress/strain sensing performance of the sensor at 0.1 N-200 N,and then a sensor array was desiged on this basis to further expand the detection range and functionality of the sensor to explore its feasibility in practical application.The porous polyurethane composite material with the performance of photothermal conversion was prepared by in-situ steam polymerization method of pyrrole monomer on the surface of porous polyurethane.In response to the requirements of the photothermal conversion material and the entire system in the application of photothermal distillation,a self-designed photothermal distillation system with simple and efficient was used to explore the influence of the density and thickness of the polyurethane composite sponge on the photothermal distillation.The feasibility of polypyrrole/polyurethane sponge was explored in practical applications by characterizing the photothermal distillation performance of it under different light intensities.The polyurethane sponge and polypyrrole was used as raw materials can reduce the cost,simplify the process and satisfy the preparation of the photothermal conversion materials in large areas.The design of photothermal distillation system and the research of photothermal distillation performance of composite sponge can optimize the whole process and increase the efficiency of photothermal distillation to more than 85%.Then the photothermal conversion material with simple processing methods can meet the application requirements of photothermal distillation and further promote polypyrrole/polyurethane sponge applied in practical live and production.Considering the application range of porous polyurethane materials with single functional properties will be limited in practical applications and the applicability to complex environments was also unsatisfactory.Self-healing porous polyurethane materials with dynamic oxime-carbamate bonds was prepared by pre-polymerization method and solution casting/template leaching method to further explore the photothermal conversion and sensor detection functions of polypyrrole/polyurethane porous composite material,where the pre-polymerization method can introduce diacetyl oxime into the polyurethane system.In this way,a bifunctional pyrrole/polyurethane porous composite material with photothermal self-healing and sensor detection was obtained.The polypyrrole was deposited in the polyurethane sponge by the method of pyrrole solution polymerization to maintain the integrity of the porous structure,and then the self-healing properties of polyurethane sponges with different crosslinking degrees can be accurately compared.Photothermal self-healing can restore more than 85%of the strength of the material,and the repaired material can still detect1%-10%strain.The self-healing mechanism of the composite sponge was revealed by characterizing the performance of photothermal conversion and photothermal self-healing and the application feasibility of porous polyurethane composite in practice was explored through the characterization of strain sensing detection.