4results about How to "Increased interlaminar shear strength" patented technology

This invention provides a sandwiched pressure hull structure and its processing method, relating to an underwater vehicle structure, including an inner hull, an outer hull, and an intermediate sandwich layer located between the inner and outer hulls. The intermediate sandwich layer includes hollow glass microspheres, reinforcing fibers, and epoxy resin. The spherical hollow glass microspheres and reinforcing fibers are uniformly mixed in the epoxy resin and placed in a fluidized state between the inner and outer hulls. After vacuum curing, they form a buoyancy material located between the inner and outer hulls. This invention addresses the problems of insufficient load-bearing capacity and low specific strength and specific stiffness of the pressure hulls of underwater vehicles in the prior art.

The application discloses a kind of PEI or PEEK-based 3D printing wave-absorbing materials and preparation method thereof.The 3D printing wave-absorbing material includes the following components by mass fraction: polyetherimide resin or polyether ether ketone resin: 45~65 parts;Electromagnetic wave absorber: 10~50 parts;Impact modifier: 4~12 parts;Flow aid: 2~8 parts;Antioxidant: 0.5~3 parts;Wherein, the electromagnetic wave absorber includes magnetic absorber and carbon-based absorber, the impact modifier and the carbon-based absorber are pre-coated to form the carbon-based absorber coated with the impact modifier on the surface, and the magnetic absorber is surface modified by silane coupling agent.The application significantly improves the mechanical properties and thermal stability of the material by using specific raw material composition and combining specific multi-layer co-extrusion and online heat treatment process.The preparation process is simple and easy to operate, and is suitable for industrial continuous production.

This invention discloses a method for preparing carbon fiber epoxy composite materials that combine high mechanical properties and a low coefficient of thermal expansion. Belonging to the field of composite materials, it addresses the technical challenge of simultaneously improving the mechanical properties and reducing the coefficient of thermal expansion of composite materials using existing carbon fiber processing methods. By non-covalently modifying carbon nanotubes with ionic liquids, unlike traditional covalent modification methods, the intrinsic strength of carbon nanotubes is preserved, constructing a multi-mechanism synergistic interface reinforcement system. This specifically addresses the key problems of traditional sizing agents having a single interfacial effect and hindered stress transmission. In this invention, flexible polyimide acts as a bridge at the interface, while rigid carbon nanotubes construct an effective armor on the fiber surface. The two form a rigid-flexible composite structure at the interface, which effectively alleviates interfacial stress concentration, significantly improves interfacial stress transmission efficiency, achieves uniform dispersion of external loads, and ultimately improves the mechanical properties of the carbon fiber epoxy composite material.

This invention relates to the field of triazine polymer preparation technology, specifically to a triazine polymer, a high-temperature resistant carbon fiber sizing agent, a preparation method, and applications. The main chain segment of the triazine polymer is a triazine structural unit. The triazine polymer is modified by synergistically introducing two different structures: R2 is a structural unit formed by removing hydroxyl hydrogen atoms from an aromatic dihydroxy compound with a rigid aromatic backbone or aromatic ketone structure, used to improve compatibility with high-temperature resistant thermoplastic resins; R3 is a structural unit formed by removing hydroxyl hydrogen atoms from an aromatic dihydroxy compound with a large-volume substituent or lactone structure, disrupting the tight packing of the molecular chain and improving the solubility of the polymer. The triazine polymer is used in the preparation of a carbon fiber sizing agent, giving the sizing agent excellent heat resistance. This sizing agent can withstand the high-temperature molding and processing environment of special engineering plastics, resulting in a novel carbon fiber sizing agent that simultaneously possesses excellent heat resistance and interfacial compatibility.