2results about How to "Crystalline" patented technology

The invention provides a high-compression-resilience skin-core composite fiber and a preparation method thereof, and relates to a composite fiber which is prepared by synthesizing novel copolyester and then utilizing a skin-core composite spinning method and has an excellent compression resilience rate. A step-by-step esterification method and a copolycondensation method are adopted to prepare copolyester A with three chain segment structures as a skin layer, and the melting point is 125-140 DEG C; copolyester B with two chain segment structures is prepared through a co-esterification and co-polycondensation method to serve as a core layer, the core layer and a skin layer are equivalent in fluidity at the same temperature, the melt index is 20-30 g / 10 min, the composite fiber with the excellent compression rebound rate is prepared through skin-core composite spinning, the mechanical strength of the fiber is larger than or equal to 2.5 cN / dtex, the compression rebound rate is larger than or equal to 85%, and the composite fiber is soft, skin-friendly and comfortable and can be used for preparing the composite fiber with the excellent compression rebound rate. And the hot air molding processing requirement can be met, and the hot air molding material can be widely applied to products such as diapers and sanitary napkins.

The present application relates to the technical field of fracturing aids, and is a temperature-controlled variable-density high-pressure-resistant proppant and a preparation method thereof.The raw materials of the temperature-controlled variable-density high-pressure-resistant proppant include a proppant, a surface modifier, a temperature-controlled polymer, an initiator and an organic solvent.The temperature-controlled variable-density high-pressure-resistant proppant is prepared by first modifying the surface of the proppant to obtain a modified proppant, then grafting and polymerizing the modified proppant with the temperature-controlled polymer, and finally post-treating the final product.The temperature-controlled variable-density high-pressure-resistant proppant can reduce the density under the response of the bottom-hole temperature, so that it is more easily transported to the deep part of a complex fracture network and uniformly laid, has a low breakage rate, can well support the fractures and promote the flow of oil and gas in the fractures.Meanwhile, the temperature-controlled variable-density high-pressure-resistant proppant still has high pressure resistance after swelling, so as to avoid being crushed to reduce the fracture width and block the seepage channel and reduce the fracture conductivity.