Zhejiang University

Zju-hangzhou Global Scientific and Technological Innovation Center

Tao Xie

Qian Zhao

Jingjun Wu

Ning Zheng

Zizheng Fang

Limei Huang

Yang Xu

Jiada Chen

Di Chen

Guogao Zhang

Xiaona Xu

Zenghe Liu

Weike Zou

Yongbo Jiang

The invention discloses a method for recycling and reusing polyurethane foam. The method includes: (1) The functionalized oligomers are obtained by adding solvent and catalyst to the polyurethane foam. (2) The functionalized oligomers are chemically modified, and the photosensitive group is introduced through the functional group reaction. The diluent, photoinitiator, and light absorber, etc. are introduced into the obtained oligomers to prepare photocurable resin. It can be used for photocurable coatings or 3D printing. This method has a fast reaction time, easy recovery of solvent and catalyst, higher value-added recycled product, good economic benefits, and social value.

Method for recycling and reusing polyurethane foam

The present invention discloses an acrylate oligomer, the acrylate oligomer is obtained by a reaction of isocyanate group-terminated oligomer and formate-terminated ethylene glycol methacrylate. After the acrylate oligomer provided by the present invention is photocured, the molecular structure, cross-linking density and other network structure characteristics of the acrylate oligomer can be changed through specific post-processing. Since the formate component formed after heat treatment has no water absorption and has a low glass transition temperature, the final material obtained after heat treatment has a lower water absorption rate and glass transition temperature. The present invention also provides a preparation method and an application method of the acrylate oligomer.

Acrylate oligomer and preparation method and application method thereof

The present invention provides a method to prepare polymer materials with interlocked porous structures by freezing and demulsification, which includes: (1) Preparing an emulsion containing uncrosslinked polymers and crosslinking agents. The uncrosslinked polymers are presented in the organic phase, and the crosslinking agents are presented in the organic phase or water phase. Under freezing, the demulsification is occurred which leads to the interaction between polymers and crosslinking agents, and the crosslinked materials are obtained. (2) After removing the ice crystals, polymer materials with interlocked porous structures are synthesized. The method provided by the present invention is simple to operate, and can well adjust the porous structures of obtained porous polymer materials. In addition, it is suitable for large scale manufacturing. At the same time, this process can form different functional porous polymer materials by simply changing the used monomers. Particularly, it can prepare melt-blown fabrics with antibacterial property, high-throughput vertical porous structures and high-temperature sterilizable feature, therefore, it can be used to manufacture medical products such as masks.

Method to prepare polymer materials with interlocked porous structures by freezing and demulsification of emulsion

The present disclosure provides a method to fabricate three-dimensional transparent glass utilizing polymer plasticity, including the following steps. In step 1, synthesize polymer-glass powder composite containing dynamic chemical bonds, the bond exchange catalyst is added during the synthesis process, and then cure to obtain a two-dimensional sheet shape I, the bond exchange catalyst is used to activate a dynamic chemical bond in step 2. In step 2, shape the two-dimensional sheet shape I obtained in step 1 into a complex three-dimensional shape II under the conditions of the effect of an external force and the activable dynamic chemical bond. In step 3, pyrolyze the composite precursor at high temperature to obtain transparent glass with complex three-dimensional shape II. The present disclosure provides a method in shaping the transparent glass with complex geometries by unique polymer plasticity in lower temperature.

Method to prepare three-dimensional transparent glass via polymer plasticity

A fabrication method and application of topological elastomers with highly branched structures, low modulus and high elasticity. The topological elastomers comprise dendritic macromolecules. The fabrication method includes direct crosslinking, post-crosslinking, grafting, and copolymerization. The performance of the elastomer can be easily tuned via changing the topology of the polymer network. The breakthrough of this invention lies in that these topological elastomers with highly branched structures are having low modulus and high elasticity, which would expand its application in the field of elastomer. Notably, the variety of topological elastomers, the versatility of curing chemistries, the availability of a wide variety of monomers, and the various polymerization methods are enabling the fabrication of topological elastomers with feasibility and efficiency.

Method for preparing topological elastomers with highly branched structures, low modulus and high elasticity

The invention relates to a method for controlling the stress distribution in a material, comprising the steps of: a, preparing a crosslinked polymer containing reversible exchange bonds; b, applying an external force to the crosslinked polymer to cause a certain strain; c, specific region of the crosslinked polymer is selectively heated while maintaining the strain. This method controls and utilizes the internal stresses which are commonly considered as unfavorable. The invention also provides a method for reading information in a polarized light field, wherein the crosslinked polymer treated by the method is transparent under natural light. The information therein can be read only under polarized light, and possesses concealment.

Method for controlling stress distribution in material and reading stress information

The present invention discloses a method for preparing stable 3D polymer objects with surface micro-nanostructures. The method includes the following steps: Step (1): Synthesizing a thermoset 2D polymer object with surface microstructures. The polymer network contains reversible exchangeable bonds. Step (2): deforming synthesized polymer to an arbitrary desired shape above the reshaping temperature with an external force applied. The permanent reshaping temperature falls in the range of 50-130&#xb0; C. and external stress is held for 5 min-24 hours Step (3): after cooling, a permanent 3D polymer object with surface microstructure is obtained. Step (2-3) can be repeated for many cycles and the 2D polymer object can be arbitrarily and cumulatively deformed to get a complex 3D structures. The polymer networks contain reversible exchangeable bonds and bond exchange catalysts in the present invention. The method disclosed in present invention is simple and efficient for preparing complex 3D polymer objects with surface micro-nanostructures.

Method for preparing 3D polymer objects with surface microstructures

The present disclosure concerns a digital corneal crosslinking technology for adjusting the corneal curvature, comprising the following steps: administering in drops a composition comprising a photoinitiator compound to the corneal stromal of the subject, locally irradiating the corneal by utilizing digital micromirror device controlled by computer. The corneal curvature can be adjusted totally or locally. The invention also discloses an apparatus for the digital corneal crosslinking. The method and apparatus is minimum invasive and can be used to accurately and efficiently adjust the corneal curvature.

Method and apparatus for adjusting corneal curvature through digital corneal crosslinking

The present invention discloses the fabrication and application of a shape memory polymer possessing transesterification-induced permanent reshaping. The ester-containing crosslinked polymer is obtained by crosslinking ester bearing polymer precursors or by reaction of monomers which yield ester bonds. The transition temperature falls between 20-150&#xb0; C. The reshaping temperature is tuned by catalyst amount and should be 20&#xb0; C. above the transition temperature. The breakthrough of the present invention lies in integrating shape memory effect and plastic deformation into the same polymer and triggering the respective function at different occasions. The permanent shape of as synthesized polymer could be modified arbitrarily and cumulatively. Therefore, the hierarchical structure which could not otherwise be obtained due to the limit of mold fabrication process should expand the practical application of SMPs.

Fabrication and application of shape memory polymer possessing transesterification induced permanent reshaping property

The present invention discloses a freezing-illumination method for preparing porous gels, comprising the steps of: (a) synthesizing the gels containing dynamic exchangeable bonds; (b) illuminating the gels under frozen state by certain wavelength light source; (c) elevating the temperature and melt the ice crystals within the gels to get the porous structure. The dynamic exchangeable bonds existing in the gels include double/multi-sulfur bond, hydrazine bond, boronic ester bond. Catalyst is also included in the gel composition to activate the bond exchange reactions under illumination. This new method for preparing porous gels is easy to operate and suitable for most kinds of gels. Meanwhile, it can spatially control the pore structure within the gels by local illumination.

Method for preparing porous hydrogel through freezing-illumination

The present disclosure concerns a digital fabricating method for constructing 3D structures, comprising the following steps: (a) precursor consist of monomers and photo-initiator is introduced into reaction cell; (b) exposing the precursor to the DLP projector for several times to gain an inhomogeneous sheet; (c) swelling the sheet in solvent to gain 3D structure. The disclosure provides a simple and easy way to produce precise 3D structure.

Growing community of inventors

Hangzhou, China

Tao Xie