3 results about "Bond rupture" patented technology

The invention discloses a low-temperature-resistant diene composite material and a preparation method thereof, and the low-temperature-resistant diene composite material comprises the following raw materials in parts by weight: 80-100 parts of modified styrene-butadiene rubber, 5-8 parts of a modified additive and 20-30 parts of modified white carbon black. A maleimide group in a modified additive molecule reacts with a furyl group of a side chain of the modified styrene-butadiene rubber to form a D-A bond so as to form dynamic crosslinking, and a dynamic crosslinking network can dissipate energy through reversible bond fracture and recombination under the action of stress, so that continuous accumulation of stress is avoided, initiation and expansion of cracks are delayed or prevented, and the service life of the rubber is prolonged. The polysiloxane chain segment of the side chain and the long-chain alkyl group on the modified white carbon black can increase the distance between the molecular chains of the styrene-butadiene rubber and weaken the interaction force between the molecular chains, thereby creating more free volume for the movement of the chain segment at low temperature; therefore, the overall glass-transition temperature of the modified rubber is obviously reduced.

This invention belongs to the field of environmental functional materials technology, and provides a self-healing, regenerable photocatalytic coating for environmentally toxic substances and its preparation method. The invention uses fluorinated polyurethane as the continuous phase, introduces reversible bonding units, and constructs a dynamic polymer network with photothermal triggering self-healing capabilities. The coating is loaded with a heterojunction composed of nitrogen-doped carbon quantum dots and bismuth tungstate, and a silica shell inhibits catalyst surface poisoning and deactivation. Furthermore, titanium carbide-based two-dimensional materials are used as conductive and photothermal aids to effectively accelerate the separation and migration of photogenerated carriers, while simultaneously generating a mild localized temperature rise under illumination, promoting the reversible bond breaking and recombination in the polyurethane network, achieving in-situ self-healing of microcracks and photo-etching damage in the coating. Additionally, the coating surface is endowed with selective enrichment and self-cleaning capabilities. The coating of this invention can maintain stable adhesion and continuous catalytic activity under long-term illumination and complex pollution environments, and has a continuous degradation capability for environmentally toxic substances such as gaseous formaldehyde.

The application discloses an S-Pt@MoS2 hollow nano reactor and a preparation method and application thereof, and belongs to the technical field of inorganic nano materials. In view of the deficiency of the existing Pt-based catalyst in two-electron oxygen reduction (ORR) catalysis, the S-Pt@MoS2 hollow nano reactor for limiting Pt nanoparticles in MoS2 cavities is prepared through a'micelle limited Pt ion' strategy, the S-Pt@MoS2 hollow nano reactor has strong Pt-S coordination, can adjust and control the oxygen adsorption mode, inhibits the O-O bond breaking, and improves the selectivity of two-electron ORR. In addition, the shell isolation effect caused by the cavity limitation can avoid the aggregation and dissolution of the Pt active sites, and improve the stability of the catalyst. The application develops a material synthesis technology based on the micelle limited strategy for precisely controlling the spatial position of the active sites, realizes the effective regulation of the ORR reaction path from four electrons to two electrons, and provides a new idea for preparing an acid electro-synthesis hydrogen peroxide efficient and durable catalyst.