77results about How to "Good shape memory" patented technology

A self-expanding medical occlusion device treats a heart defect in a patient and is inserted into the body in minimally invasive fashion using a catheter system, and includes a braiding of thin threads which exhibits a first preliminarily definable shape as the occlusion device is being inserted into the patient's body and a second preliminarily definable shape in the implanted state, whereby the occlusion device is in a collapsed state in the first shape of the braiding and in an expanded state in the second shape of the braiding. The threads of braiding are composed of a shape memory polymer composite such that braiding deforms from a temporary shape to a permanent shape in consequence of an external stimulus, whereby the temporary shape is given in a first profile form of the braiding and the permanent shape is given in a second profile form of the braiding.

A self-expanding medical occlusion device treats a heart defect in a patient and is inserted into the body in minimally invasive fashion using a catheter system, and includes a braiding of thin threads which exhibits a first preliminarily definable shape as the occlusion device is being inserted into the patient's body and a second preliminarily definable shape in the implanted state, whereby the occlusion device is in a collapsed state in the first shape of the braiding and in an expanded state in the second shape of the braiding. The threads of braiding are composed of a shape memory polymer composite such that braiding deforms from a temporary shape to a permanent shape in consequence of an external stimulus, whereby the temporary shape is given in a first profile form of the braiding and the permanent shape is given in a second profile form of the braiding.

The invention relates to a bio-based thermoplastic elastomer with shape memory function and a preparation method thereof. The bio-based thermoplastic elastomer with shape memory function is prepared from the following raw materials in parts by mass: 30-80 parts of polylactic acid, 20-70 parts of epoxidized natural rubber, 0.2-2 parts of antioxidant, 0.02-2 parts of boron trifluoride etherate and 0.1-3 parts of crosslinking agent. The preparation method comprises the following steps: uniformly mixing the polylactic acid, antioxidant, boron trifluoride etherate and epoxidized natural rubber at 150-190 DEG C, and adding the crosslinking agent under high-speed shearing actions to vulcanize the rubber in situ, thereby obtaining the bio-based thermoplastic elastomer with shape memory function. The rubber phase and plastic phase of the bio-based thermoplastic elastomer respectively appear a continuous phase structure. The structure endows the material with excellent shape memory function and mechanical properties, so that the shape fixation rate is up to 100%, and the shape recovery rate is up to 90% or above.

A method for producing a polybutylene terephthalate film by an air-cooled inflation method of inflating a tube of a molten polybutylene terephthalate resin extruded from an annular die by the injection of air, the resin-extruding pressure being 8.3 to 13.7 MPa, and the resin-extruding temperature being a temperature ranging from the melting point of the polybutylene terephthalate resin −15° C. to the melting point −5° C.

A catheter assembly (10) having a catheter (12) with lumens (20a,20b), extension tubes (14a,14b) and a hub (16). Distal ends (36) of the extension tubes and the proximal end (24) of the catheter are secured in and to the hub. Fittings (50) are first affixed in the distal ends of the extension tubes and have annular collars (56) that are embedded in the hub when the hub is molded over the distal ends of the extension tubes during manufacturing. An array of annular barbs (60) secure the cylindrical portion (52) of each fitting in the respective extension tube distal end (36).

A torqued archwire for use in an edgewise orthodontic bracket system. The archwire is substantially rectangular in cross-section, is made of titanium-based alloy and has a plurality of segments, including an anterior segment which is sized to cooperate with brackets attached to a person's central and lateral teeth. Positive torque is built into this anterior segment, with substantially the same positive torque being used across the entire length of the segment. Extending from the respective ends of the anterior segment are a pair of transition segments, in which the torque built into the archwire is approximately zero. Posterior segments of the archwire, which extend distally from the transition segments, each have a negative built-in torque, with substantially the same negative torque being used across the entire lengths of these segments. For ease of reference by an orthodontist, the “active” anterior segment of the archwire is laser etched or colored with non-toxic ink.

The invention relates to the technical field of intelligent materials, and provides a shape memory composite material based on polyhydroxyalkanoate. The composite material comprises the following components in parts by weight: 30-70 parts of polyhydroxyalkanoate, 30-70 parts of polyurethane, and 0-10 parts of compatilizer, wherein the molecular weight of polyhydroxyalkanoate is greater than 10,000 g / mol; polyurethane is prepared by isocyanate and micromolecular alcohol or amine with the molecular weight less than 600 g / mol; and the content of isocyanate and micromolecular alcohol or amine in polyurethane is greater than 70 wt%. The invention further provides a preparation method of the material based on polyhydroxyalkanoate, and the application of the material based on polyhydroxyalkanoate in the aspects of biomedical engineering, textile, toys and daily supplies. The material has good biological compatibility, does not form thrombi when contacted with blood, is integrated with tissue cells well, and has a shape memory function, the shape fixing rate is greater than 80%, and the shape recovery rate is greater than 80%.

The invention provides a PVC-U (polyvinyl chloride unplasticized) tube with a shape memory function and a production method and application thereof. The PVC-U tube with the shape memory function is made from, by weight, 100 parts of polyvinyl chloride resin, 1.5-8.0 parts of a thermal stabilizer, 0.1-60 parts of a lubricant, 0-8 parts of a plasticizer, 0.5-8 parts of a processing modifier, 1-10 parts of a toughener, 0.02-5 parts of a crosslinker, 0-6 parts of an acid absorbent, and 0-30 parts of a filler. The PVC-U tube has the good shape memory function and is particularly suitable for the repair of a damaged conduit under micro-excavation or zero excavation. In addition, the production method of the PVC-U tube is simple and low in cost.

The invention discloses a composite nanometer fiber film formed by compositing chitosan, gelatin and shape memory polyurethane; the chitosan and gelatin are prepared by the weight ratio of (0.5-2):1; the total weight of the chitosan and gelatin and the weight of the shape memory polyurethane are prepared by the ratio of (0.2-2):1; the composite nanometer fiber film preparation method comprises the following steps: dissolve the chitosan, gelatin and shape memory polyurethane into a solvent so as to obtain a homogeneous solution; using a static spinning method to process the homogeneous solution so as to obtain the composite nanometer fiber film; carrying out proper after treatment for the composite nanometer fiber film. The composite nanometer fiber film is good in cell compatibility, wide spectrum antibiosis activity, haemostasis performance, permeability, mechanical strength, shape memory function, water vapor transmittance, heat stability and imbibition rate, and can be applied as biology medical dressing.

Water-triggered shape memory polymers based on poly(ε-caprolactone) (PCL) and poly(ethylene glycol) (PEG) multiblock hybrid thermoplastic polyurethanes. Urethane linkages were formed through the addition reaction between isocyanate groups of the lysine methyl-ester diisocyanate (LDI) and the hydroxyl groups of either (PEG) or PCL diol.

The invention discloses a preparation method of novel rapid-responded shape memorizing polyurethane. The novel rapid-responded shape memorizing polyurethane is prepared by pre-polymerizing diisocyanate and polyester polyol, and then polymerizing with bi-selenium glycol block. The novel rapid-responded shape memorizing polyurethane comprises the following components in parts by mass: 50-100 parts of polyester polyol, 25-50 parts of diisocyanate, 12-15 parts of bi-selenium glycol, 100-200 parts of an organic solvent, and 0.05-0.1 part of a catalyst. The method specifically comprises the following steps: 1, distilling polyester polyol for 3-5h in a vacuum condition in order to remove water; and controlling the vacuum degree to be not greater than 0.08MPa; 2, sequentially mixing polyester polyol, diisocyanate, the organic solvent and the catalyst; heating in a nitrogen atmosphere until the temperature is 60-75 DEG C; and stirring for 3-6h; and 3, adding bi-selenium glycol; maintaining thereaction temperature at 60-75 DEG C; and continuously stirring and reacting for 3-6h under nitrogen protection. The shape memorizing polyurethane prepared by the method is high in shape recovery rate,and has a good memorizing effect.

The invention provides a low-cost and stable lithium battery silicon negative electrode and a preparation method thereof. Silicon-based nanoparticles, liquid silicone rubber and ethylene-vinyl acetatecopolymer are uniformly mixed up according to a mass ratio of 10: 3: 1, and then are heated, melted and dispersed. In this way, silicon-based nanoparticles are uniformly dispersed in the melt. Afterthat, a curing agent, graphene powders and carbon fibers are added into the melt prefabricated in the step (1), and the mixture is ultrasonically dispersed to obtain a slurry. The slurry is coated onthe surface of a negative current collector, and then is cured at 80 DEG C for 2 hours. After that, the material is dried, slit and tabletted to obtain the lithium battery silicon negative electrode.According to the invention, nano silicon is directly dispersed in the deformation memory silicone rubber to prepare the silicon negative electrode. The system has self-repairing performance and shapememory performance at a certain temperature. The problem of silicon expansion fragmentation is well solved. The preparation process is greatly simplified, and the preparation cost is reduced. The defects that an existing technology for solving the problem that a silicon negative electrode is prone to expansion is complex and high in cost, and the size is increased after porosity is achieved are overcome.

Water-triggered shape memory polymers based on poly(ε-caprolactone) (PCL) and poly(ethylene glycol) (PEG) multiblock hybrid thermoplastic polyurethanes. Urethane linkages were formed through the addition reaction between isocyanate groups of the lysine methyl-ester diisocyanate (LDI) and the hydroxyl groups of either (PEG) or PCL diol.

The invention discloses a remoldable bismaleimide resin and an application thereof. The remoldable bismaleimide resin is prepared by the following steps: blending 2-allylphenyl glycidyl ether with terephthalic acid in acetonitrile, carrying out an esterification reaction with a quaternary ammonium salt as a catalyst to obtain a bis(3-(2-allylphenoxy)-2-hydroxypropyl)terephthalate containing a reversible dynamic group; and uniformly mixing the bis(3-(2-allylphenoxy)-2-hydroxypropyl)terephthalate with bismaleimide, and curing the obtained mixture to obtain the remoldable bismaleimide resin. Theremoldable bismaleimide resin prepared in the present invention has excellent heat resistance and excellent mechanical properties, and can be remolded under a hot pressing condition. The preparation method of the remoldable bismaleimide resin has the characteristics of wide sources of raw materials, and simple process, and the has remoldable bismaleimide resin broad application prospects in industrial fields of aerospace, transportation, electronic information, new energy and insulated electrics.

The invention discloses a polyurethane / epoxy resin blend with shape memory, self-repairing and recyclability functions and a preparation method thereof. The polyurethane / epoxy resin blend is a homogeneous blend of polyurethane and epoxy resin or a two-phase phase separation blend formed by mixing the polyurethane and the epoxy resin and then performing crosslinking and curing with a curing agent,wherein the polyurethane is a linear polyurethane material containing a disulfide bond in the main chain, the epoxy resin is an epoxy resin pre-polymer with a side group containing a furan ring, and the curing agent contains a maleimide group. The preparation method of the polyurethane / epoxy resin homogeneous blend is as follows: dissolving the polyurethane and the epoxy resin pre-polymer in an organic solvent, performing stirring and blending at a temperature of 60-80 DEG C, and performing drying at a temperature of 60-80 DEG C after uniform stirring to obtain the blend. The shape memory, self-repairing and recovery characteristics of a polyurethane material are improved by a blending method, mechanical properties of polyurethane are enhanced at room temperature, and recyclability of thepolyurethane at high temperature is not affected.

The invention discloses a biodegradable cryogel dressing as well as a preparation method and application thereof, and belongs to the technical field of biomedical materials. Amino compounds are selected as main components, and the selected amino compounds have good biocompatibility and can be degraded in organisms. Therefore, the amidation reaction of amino and carboxyl in the amino compound is catalyzed by EDC hydrochloride and NHS to form a basic network structure of the cryogel. The cryogel dressing is holes communicating with each other in a free state, compared with the cryogel dressing in a shape free state, the cryogel dressing in a shape fixed state is a collapsed and closed hole, but a cryogel dressing sample still keeps an undamaged network structure. The preparation method disclosed by the invention is simple and low in cost, the biodegradable cryogel dressing is easy to carry and biodegradable, and the prepared cryogel dressing can be used for quickly stopping bleeding andhas huge potential in serving as a novel hemostatic for promoting wound healing.