66results about How to "High degree of peeling" patented technology

The invention provides an extrusion stretching type pre-coating film and a preparation method thereof. The pre-coating film sequentially consists of a functional layer, a core layer, a bonding layer and a hot melting glue layer from top to bottom, wherein the functional layer material is made of adhesive polypropylene masterbatch and a film-level homo-polypropylene; the core layer material is film-level homo-polypropylene; the bonding layer material is ethylene-methyl acrylate copolymer; the hot melting glue layer material is prepared from antioxidants and ethyl-vinyl acetate polymers. The extrusion stretching type pre-coating film is prepared by using a bidirectional stretching process and the coating by using a bottom sizing agent is eliminated, so that the process is simplified, and the mechanical strength and the stripping degree of the prepared pre-coating film are further improved, and the pre-coating film is more environmental friendly.

The invention discloses a preparation method of Pt-Co / C-single-layer graphene for a fuel cell, belongs to the chemical synthesis field, and relates to a preparation method of graphene. The Pt-Co / C-single-layer graphene for the fuel cell is prepared by the following steps: (1), preparation of graphite oxide; (2), pre-treatment of active carbon XC-72; and (3), preparation of an rGO-XC-72 composite carrier-loaded Pt-Co alloy nano particle. The metal alloy nano particle-graphene and XC-72 active carbon composite catalyst prepared by utilizing a microwave ethylene glycol auxiliary reduction method is simple and easy to implement, and is high in efficiency. Moreover, the obtained graphene has a single-layer structure and the alloy particle has uniform particle diameter distribution and an average particle diameter of 1.5 nm. The catalytic activity of the nano particle can be improved by interaction with the XC-72 active carbon as well as electronic modification to the metal nano particle. And obtained catalyst has excellent oxygen-reduction electro-catalysis performances.

The invention provides a method for preparing graphene oxide through an ultrasonic-assisted process. The method comprises the following steps: in a low temperature stage, subjecting natural flake graphite to complete ultrasonic dispersion in a mixed acid solution of concentrated sulfuric acid and concentrated phosphoric acid, slowly adding a small amount of potassium permanganate in the process of stirring, and carrying out preoxidation under an ultrasonic condition; and in the high temperature stage, continuously adding potassium permanganate under stirring, carrying out deep oxidation so as to obtain graphite oxide, then carrying out centrifugal washing until the graphite oxide is neutral, and ultrasonically exfoliating the graphite oxide so as to obtain the graphene oxide. The method provided by the invention uses the ultrasonic-assisted process to prepare the graphene oxide, so the preparation time can be effectively saved; energy is saved; meanwhile, the interlamellar spacing of the graphite oxide is effectively improved. The graphene oxide prepared by using the method provided by the invention can be used for preparation of high-strength lightweight composite materials, catalyst carriers, adsorbent carriers, etc. The graphene obtained by reduction can be used for preparation of graphene composite materials like energy storage materials, sensors and super-capacitors.