Study On Manufacture And Properties Of PP/Collagen Anti-adhesion Hernia Mesh

Hernia mesh belongs to medical textile,which is a combination of textile technology and biomedicine.Hernia mesh has high value of innovation,science and technology,broad application.Hernia is very harmful to the human body.Without herniorrhaphy,it will affect the daily life or even cause death.More than 5 million people are diagnosed with hernia every year.The demands for hernia mesh also increasing year by year.Nowadays,the biggest problem of hernia mesh is that it is prone to adhesions.It is directly related to the repair of the postoperative situation.Therefore,it's very important to study hernia mesh.Polypropylene is a commonly material,which has stable physical and chemical properties,and has good biocompatibility and biological stability.Therefore,in this paper,polypropylene was chosen as material of hernia mesh.And 3 kinds of structures were designed.The influence of heat setting process on structural parameters and mechanical properties of polypropylene was studied.Collagen is a new kind of hernia repair material.Collagen is easy to degrade and has good biocompatibility.In order to reduce foreign body,adhesion and chronic pain and other complications,collagen was selected as anti-adhesion layer.Collagen was spun on polypropylene base.One side of the compound mesh is polypropylene and the other side is collagen nanofiber membrane.At the same time,the influence of the electrospun process on the appearance of the spun nanofibers was studied.The cytotoxicity and anti-adhesion of c compound mesh were evaluated by cell experiment.The main research contents can be summarized as follows:(1)Structure design,preparation and finishing of hernia mesh.Three different structures were designed,which were atlas stitch,atlas based on tricot stitch,varied tricot stitch.Polypropylene monofilament which the diameter is 0.15 mm was twining around 4 pan heads.And then mesh was been knitted.In order to improve the stability of the structure,the physical and mechanical properties of the mesh,the heat setting was carried out.The optimal process parameters of temperature,time and widening rate in the heat setting were discussed.(2)Study on heat setting process parameters of polypropylene meshThe basic properties,mechanical properties and bending stiffness of the mesh after heat setting were studied.Basic properties include thickness,surface density and porosity.Mechanical properties include tensile,tearing,bursting and tensile strength of suture.The results show that: the optimum process parameters of the atlas stitch mesh on basic properties are 130 ?,10 min,8.60 %(the lengthwise elongation)and 6.41 %(lateral extension).The optimum process parameters of the atlas based on tricot stitch and varied tricot stitch mesh on basic properties are 120 ?,8 min,8.60%(the lengthwise elongation)and 6.41%(lateral extension).The optimum process parameters of the atlas stitch mesh on bending stiffness are 140 ?,12 min,0%(the lengthwise elongation)and 0%(lateral extension).The optimum process parameters of the atlas based on tricot stitch and varied tricot stitch mesh on bending stiffness are 120 ?,8 min,3.23%(the lengthwise elongation)and 2.56%(lateral extension).By comprehensive analysis of mechanical properties,it is concluded that the optimum process parameters of the atlas stitch,atlas based on tricot stitch,varied tricot stitch mesh are 120 ?,8 min,0%(the lengthwise elongation)and 0%(lateral extension).(3)Manufacture and properties of patterned electrospinning anti-adhesion of collagen/PEO membrane.The collagen solution was spun onto the aluminum foil by electrospinning to form an anti-adhesion membrane.The effect of polymer concentration,solute ratio,voltage and receiving distance on the morphology of nanofibers was investigates.When the concentration of the solution is 6%,the content of PEO is 30%,voltage is 12 KV,distance is 20 cm,the unevenness of fiber thickness is the smallest,and the evenness is uniform.The results of infrared spectroscopy showed that there were collagen and PEO in the fiber,and there was a strong hydrogen bond between the collagen and the PEO chain.Thermogravimetric analysis showed that the mass fraction of collagen in collagen /PEO composite fiber membrane was 73%,which was near the theoretical value of collagen content(70%)in initial spinning solution.(4)Study on anti-adhesion of electrospinning collagen /PEO micro nanofiber meshCollagen /PEO membrane was spun on polypropylene substrate by optimal electrospinning process parameters.Cytotoxicity and anti-adhesion of collagen /PEO membrane were evaluated by in vitro cell culture method.The composite mesh was cultured for 1,2,4 and 7 days.The CCK-8 kit was used to test the results.The results showed that the 3 kinds of composite meshes had no cytotoxicity.The composite mesh was cultured of 60 and 120 and 240 min.SEM photos were shot for the composite mesh.The results showed that: when the culture time is 60 min,3 kinds of composite meshes had little adhesion,when the culture time is 120 and 240 min,the quantity of adhesion is not much,especially t atlas stitch and collagen /PEO composite meshes.