51 results about "Isothermal crystallisation" patented technology

The invention relates to a method for preparing a high-oriented gamma phase polyvinylidene fluoride PVDF thin film. The method comprises the following steps of: 1) first, casting a thin film for PVDF liquor to heat, insulate and eliminate thermal history, and quickly cooling the PVDF thin film at 50 DEG C / min to 160-170 DEG C; and 2) applying pressure to melt by a polymethylsiloxane plate to apply a shear stress, standing at 160-170 DEG C, wherein the crystallizing form at 160-163 DEG C is converted to alpha crystallizing form, and conversion from alpha crystallizing form to gamma crystallizing form occurs at 168-170 DEG C; the crystallizing crystal nucleus is alpha crystal nucleus at 164-167 DEG C, and the crystallizing form at 168-170 DEG C is gamma crystallizing form. A polarizing microscope, a scanning electron microscope and an infrared spectrometer represent crystallization of the melt in a shear stress field and a crystal structure after crystallization, so that the method is simple in process, and simple, convenient and accessible, and the problem that pure gamma phase PVDF thin film cannot be obtained by isothermal crystallization is solved. The gamma phase PVDF thin film which is high in purity, high in orientation and excellent in thermodynamic property can be prepared.

A method is provided for making large, uniform and individual crystals from aqueous solutions including the steps of obtaining a concentrated aqueous solution by means of evaporation; rapidly cooling the solution from a post-evaporation high temperature to a first lower temperature, wherein the first lower temperature is lower than the post-evaporation high temperature and further wherein the first lower temperature is an isothermal crystallization temperature of said solution; generating a batch of initial nuclei by inducing nucleation at the first lower temperature and starting crystal growth; uniformly spreading the initial nuclei into a bulk solution; maintaining simultaneous and rapid growth of crystals from the nuclei at the first lower temperature for a predetermined length of time; continuing the growth of the crystals to produce large, uniform and individual crystals for a predetermined length of time at a temperature that varies gradually from between a first lower temperature to a second lower temperature, wherein the second lower temperature is a temperature lower than the first lower temperature and further wherein the second lower temperature is an end temperature of crystallization; and recovering the large, uniform and individual crystals. Parameters and a system for producing lactose monohydrate crystals using the method are also provided.

The invention relates to a preparation method of calcium metaphosphate porous bioceramic. The preparation method is characterized by using calcium oxide and phosphoric acid as initial reactants to synthesize monocalcium phosphate monohydrate (Ca(H2PO4)2.H2O, MCPM) powder by means of isothermal crystallization chemical precipitation according to the formation mechanism of calcium metaphosphate; carrying out thermal treatment on the powder at different temperatures respectively to synthesize monocalcium phosphate (Ca(H2PO4)2, MCPA) powder and calcium dihydrogen pyrophosphate (CaH2P2O7, CDPP) powder; preparing the calcium metaphosphate porous ceramic from the powder synthesized respectively in the condition of controlling the molding process and the sintering mechanism (such as the molding pressure of the sample, and the temperature raising rate of the initial thermal treatment). The gas released when different crystal water contained in the raw material is decomposed is used as a pore forming agent, and the synthesis method of the powder and the preparation process of the porous body are controlled to obtain the calcium metaphosphate porous ceramic prepared by adopting the preparation method disclosed by the invention.

The invention belongs to the field of polymer composite materials, and particularly relates to a completely stereotyped high-toughness polylactic acid stereocomplex and a preparation method thereof. The polylactic acid stereocomplex provided by the invention is prepared by carrying out melt blending on raw materials and then carrying out isothermal crystallization, wherein the raw materials comprise: 50 parts by weight of poly-L-lactic acid; 50 parts by weight of poly(D-lactic acid); 10-20 parts by weight of a compatible blend; and 10-20 parts by weight of a toughening agent; wherein the compatible blend comprises polyvinyl acetate and / or poly-racemic lactic acid; the toughening agent comprises a vinyl acetate-vinyl laurate copolymer and / or a racemic lactic acid-caprolactone copolymer; andthe temperature of isothermal crystallization is 90-140DEG C. According to the invention, the stereocomplex crystallinity and toughness of the polylactic acid stereocomplex are obviously improved bystrictly controlling the dosage ratio of the poly-L-lactic acid to the poly(D-lactic acid) in the raw materials, adding the compatible blend and the toughening agent and adopting an isothermal crystallization process.

The invention discloses a high-strength super-tough polylactic acid nano-pore foaming material and a preparation method thereof. The method comprises the following steps: firstly, carrying out vacuumdrying on a polylactic acid raw material, then carrying out hot pressing on polylactic acid to form a plate, and carrying out isothermal crystallization at 100-120 DEG C for 3-5 hours; cutting the polylactic acid plate subjected to isothermal crystallization into small sample strips, putting the small sample strips into the middle of a pressure-induced flow forming mold, and carrying out low-temperature pressure-induced flow forming for 5-10 minutes under the conditions that the temperature ranges from 80 DEG C to 130 DEG C and the pressure ranges from 30 MPa to 300 MPa; and putting the samplestrips subjected to pressure-induced flow forming into a high-pressure kettle, performing sealing, adding a physical foaming agent, soaking for 4-12 hours under the conditions that the temperature ranges from 100 DEG C to 120 DEG C and the pressure ranges from 8 MPa to 20 MPa, and obtaining the polylactic acid nano-pore foaming material through rapid pressure relief. The polylactic acid preparedby the method provided by the invention has a large number of uniformly distributed nanopores, and has excellent mechanical properties.

The invention relates to a preparation method of an MgCl2-doped annular gamma-phase polyvinylidene-fluoride-base composite film. The preparation method comprises the following steps: 1) preparing a polyvinylidene fluoride / MgCl2 blend solution by using N,N-dimethylformamide (DMF) as a solvent; 2) preparing blend solutions with different mass percents into films on a hot stage, sandwiching each film between two transparent glass plates to prepare a sandwich structure; 3) eliminating the heat history of the blend films with different mass percents in the step 2), carrying out cooling and isothermal crystallization, and applying until the blend films completely crystallize; and 4) characterizing the gamma crystal form and gamma crystal form topographic characteristics of the blend films by using an infrared spectroscopy, a Raman spectroscopy, a differential scanning calorimeter, a polarized light microscope, a scanning electron microscope and other means. The method has the advantages of simple main technique and short preparation period, is convenient to operate, and can prepare the gamma-polyvinylidene-fluoride-base composite film with large size and special annular shape; and the gamma-polyvinylidene fluoride has the unique electric properties different from alpha-polyvinylidene fluoride.

The invention discloses a simple preparation method for a nanometer rod or nanometer wire of a piezoelectric polymer P(VDF-TrFE). The nanometer rod or nanometer wire of the polymer is prepared by combining the dewetting effect of a substrate with the diffusion limitation effect of a film in the nonisothermal crystallization process on the basis that the film of the piezoelectric polymer is prepared by a solution method. According to the preparation method, needed devices are simple, operation is convenient, and the prepared nanometer rod or nanometer wire of the polymer is high in the degree of crystallization and good in the piezoelectric effect, can grow in specific direction, and can be applied to related piezoelectric type sensors, flexible nanometer power generation systems and the like.

The present invention provides an ethylene polymer having a viscosity average molecular weight of 100×104 or more and 1,000×104 or less, in which a ratio between an isothermal crystallization time at 125° C. and an isothermal crystallization time at 123° C. obtained under specific isothermal crystallization time measurement conditions is 3.5 or more and 10.0 or less, and a degree of crystallization obtained using a differential scanning calorimeter (DSC) is 40% or more and 75% or less.

The invention relates to a preparation method of a 100% gamma phase PVDF (polyvinylidene fluoride) film, and the method comprises the following steps: modified illite and PVDF granules are subjected to first mixing treatment, and the modified illite is obtained by carrying out surface activation treatment on illite; film-forming treatment is performed on a first mixed treatment product; drying isperformed on a film-forming treatment product; a drying treatment product is subjected to fusion treatment so as to eliminate heat history; and isothermal crystallization treatment is performed on a fused treatment product under the condition that the temperature is 158-168 DEG C so as to obtain the gamma-phase PVDF film. The method can be used for preparing a 100% gamma phase PVDF material, highin crystallization rate, high in efficiency, low in cost and suitable for large-scale popularization and application.

The invention relates to a large-size glass product with a natural ice crystal imitating effect and an industrial casting method of the large-size glass product. The product is a lead-free glass casting with the weight larger than or equal to 100 kg, dendritic crystal-shaped or snowflake-shaped devitrified phases which are formed by growing calcium fluoride as crystal nucleuses and are distributed randomly are arranged in the product, and the three-dimensional aesthetic effect imitating natural ice crystals is achieved. The method comprises the following steps: mixing lead-free glass particles with a calcium fluoride nucleating agent with a specific particle size, and filling a mixture into a special mold with a three-layer composite structure and a temperature monitoring function; and executing a four-stage programmed thermal regulation including melting homogenization, nucleation cooling, isothermal crystallization and super-slow multi-step annealing, wherein the melting and heat preservation time and the maximum thickness of the product meet the quantitative relation of t = k.H. Through systematic collaboration of materials, molds and processes, the technical problems that crystallization in large-size glass is not uniform and cracking is easily caused by thermal stress are solved, high yield and stable mass production of products of 500 kg or above are achieved, and the method is suitable for the fields of high-end buildings, art devices and decoration.

An ethylene terephthalate type polyester resin for forming containers, having an intrinsic viscosity in a range of 0.65 to 0.85 dL / g, a total content of a monohydroxyethyl terephthalate and a bishydroxyethyl terephthalate of less than 0.005% by weight, (a) a heat of fusion of not more than 50 J / g, a end temperature of melting peak of not higher than 270° C. and a crystallinity of less than 0.48, or (b) an acetaldehyde concentration of 2 to 10 ppm, and satisfying at least either one of (i) a peak time of crystallization is not longer than 360 seconds and the crystallization energy (ΔH) is not less than 30 J / g in the isothermal crystallization at 210° C., or (ii) components having molecular weights of not larger than 10000 are contained in not less than 8%. The polyester resin effectively prevents the problems such as a fouling of the metal mold in forming containers or a decrease in the productivity. A decreased acetaldehyde concentration provides excellent flavor-retaining property. Further, the heat-setting and mouth portion crystallization can be efficiently conducted making it possible to produce heat-resistant containers maintaining good productivity.

The present invention provides an ethylene polymer, wherein the viscosity-average molecular weight as determined according to specific conditions for measuring the isothermal crystallization time is 100 * 104 to 1,000 * 104 (inclusive), the ratio of the isothermal crystallization time at each of 125 DEG C and 123 DEG C is 3.5 to 10.0 (inclusive), and the degree of crystallization as determined from differential scanning calorimetry (DSC) is 40 to 75% (inclusive).

The present invention provides a biodegradable resin composition and a biodegradable molded article including the same, wherein the biodegradable resin composition includes: a first biodegradable resin including a first repeating unit derived from a diol, a second repeating unit derived from aromatic dicarboxylic acid, and a third repeating unit derived from aliphatic dicarboxylic acid; and a crystallization accelerator, wherein the crystallization accelerator is included in a content of 100 ppm to 50,000 ppm, and an isothermal crystallization time at 90° C. according to Measurement Method 1 (see the detailed description) is 10 seconds to 900 seconds.

The invention discloses a polypropylene-based high-voltage direct-current cable material and a modification and crystallization temperature regulation and control method. A nucleating agent modified polypropylene base material can be prepared by the following steps: (1) adding polypropylene and a nucleating agent into a double-screw blending machine for melt blending, and extruding after uniformlyblending by double screws, so as to obtain a polypropylene master batch containing the nucleating agent, wherein the mass of the nucleating agent accounts for 5-10% of the total mass; and (2) addingthe polypropylene master batch containing the nucleating agent and polypropylene into a double-screw blending machine, carrying out melt blending, uniformly mixing through double screws, and extrudingto obtain isotactic polypropylene containing the nucleating agent. According to the crystallization temperature regulation and control method, in the homogenization section of the cable extrusion process, the crystallization temperature and crystallization time in the polypropylene cooling and shaping process are regulated and controlled through given temperature index design control in an isothermal crystallization or non-isothermal crystallization working mode.

The present application relates to a kind of polyethylene terephthalate foamed materials and its preparation method, the preparation method includes the following steps: polyethylene terephthalate material is heat pressed, and the preform of molten state is obtained;The preform of molten state is treated with melt isothermal crystallization and quenching, and sheet material is obtained;And the sheet material is treated with foaming, and polyethylene terephthalate foamed material is obtained.The present application uses melt isothermal crystallization treatment, can improve the melt strength in the foaming process of polyethylene terephthalate, strengthens its foaming performance, simultaneously can also be realized by strengthening bubble nucleation and controlling bubble growth to adjust the bubble morphology of foamed material, so can obtain the polyethylene terephthalate foamed material of bubble size uniform and controllable foaming ratio.

The present application relates to a kind of polyethylene terephthalate-2,5-furandicarboxylic acid glycol copolyester foamed material and its preparation method, the preparation method includes the following steps: polyethylene terephthalate-2,5-furandicarboxylic acid glycol copolyester material is heat pressed, and the preform of molten state is obtained;The preform of molten state is treated with melt isothermal crystallization and quenching, and sheet material is obtained;Sheet material is treated with foaming, and polyethylene terephthalate-2,5-furandicarboxylic acid glycol copolyester foamed material is obtained.The present application uses melt isothermal crystallization treatment, can improve the melt strength in the foaming process of polyethylene terephthalate-2,5-furandicarboxylic acid glycol copolyester, strengthens its foaming performance, simultaneously can also be realized by strengthening bubble nucleation and controlling bubble growth to adjust the bubble morphology of foamed material, so polyethylene terephthalate-2,5-furandicarboxylic acid glycol copolyester foamed material with uniform bubble size and controllable foaming ratio can be obtained.

Heat-shrinkable polyester film, derived from a first polyester resin and a second polyester resin as a plurality of polyester resins exhibiting different crystallinity, which are reaction products of a polyvalent carboxylic acid and a polyalcohol, wherein the heat-shrinkable polyester film fulfills the following features (A) to (E): (A) the first polyester resin is an amorphous polyester resin in which the polyvalent carboxylic acid contains at least terephthalic acid, and if a total amount of the polyalcohol is assumed to be 100 mol%, the reaction amount of ethylene glycol is in the range of 50 mol% or more and below 90 mol%; (B) the second polyester resin is a crystalline polyester resin in which the polyvalent carboxylic acid contains at least terephthalic acid, and if the total amount of the polyalcohol is assumed to be 100 mol%, a reaction amount of ethylene glycol is 90 mol% or more; (C) the heat-shrinkable polyester film is a heat-shrinkable polyester film which, when an isothermal crystallization measurement is performed by DSC at 150 °C, including a cooling process at a constant temperature, an exothermic peak occurs within 12 minutes of the start, including the cooling process time; (D) the heat-shrinkable polyester film is a heat-shrinkable polyester film in which, when an isothermal crystallization measurement is carried out by DSC at 150 °C, including a cooling process at a constant temperature, the amount of heat corresponding to the obtained exothermic peak area is in the range of 5 to 35 J / g; and (E) the heat-shrinkable polyester film is a heat-shrinkable polyester film in which a thermal shrinkage ratio in one principal shrinkage direction, measured under the thermal shrinkage conditions of immersion in hot water at 80 °C for 10 seconds, is in the range of 20% to 60%, wherein a weight-based mixing ratio of the first polyester resin / second polyester resin is in the range of 20 / 80 to 80 / 20, wherein the mass of the agglomerates as blockage resistance according to APR Document Code: PET-S-08 is less than 5%, and wherein the thickness of the heat-shrinkable polyester film is 25 to 70 µm.

The invention discloses a thermoplastic polypropylene cable isothermal crystallization extrusion-molding method and belongs to the field of high voltage and insulation. The method includes the following steps that (1) a thermoplastic polypropylene material is dried; (2) a threaded rod of a catenary extrusion unit is pre-heated; (3) the compression ratio of the threaded rod is adjusted, and mixingis started; (4) a water-cooling type device is installed on the extrusion unit, and thus a complete temperature control system is established; (5) the temperature is decreased to the constant temperature in a water-cooling control mode and the constant temperature is kept for 10 minutes; and (6) by means of water-cooling type segmented temperature decreasing, a polypropylene cable insulation material is obtained after isothermal crystallization is performed for 10 minutes in the temperature of 126 DEG C. A polypropylene cable sample is high in electrical performance after isothermal crystallization for 10 minutes in the temperature of 126 DEG C, and the application value is significant in the aspect of wire and cable insulation.

The invention relates to a biodegradable resin composition and a biodegradable non-woven fabric. The present invention provides a biodegradable resin composition comprising: a first biodegradable resin comprising a first repeating unit derived from a diol, a second repeating unit derived from an aromatic dicarboxylic acid, and a third repeating unit derived from an aliphatic dicarboxylic acid; and a crystallization promoter, in which the crystallization promoter is included in a content of 100 ppm to 50,000 ppm, and the isothermal crystallization time at 90 DEG C according to measurement method 1 in the specification is 10 seconds to 900 seconds.

The present invention belongs to the technical field of functional polymer materials, and discloses a low melt index and low shrinkage PPH sheet and a preparation method thereof. The preparation method comprises the following steps: adding homopolymerized polypropylene and organic-inorganic composite β-nucleating agent-reinforced particles into an extruder for uniform melt blending, then extruding into a mold, rapidly quenching to an isothermal crystallization temperature at a rate of 30 to 60°C / min under a pressure of 5 to 20MPa for β-crystallization reaction, and then cooling to room temperature to obtain a low melt index and low shrinkage PPH sheet. The organic-inorganic composite β-nucleating agent-reinforced particles are obtained by cross-linking an acid-terminated prepolymer obtained by a catalytic reaction of diamino-terminated polydimethylsiloxane and a dibasic acid through an amino-modified inorganic nucleating agent. The PPH sheet of the present invention can significantly enhance its acid and alkali resistance and physical properties by using specific organic-inorganic composite β-nucleating agent-reinforced particles for β-crystallization reaction and enhanced modification.

A polyester resin containing dicarboxylic acid structural units and diol structural units, more than 0 mol% and 20 mol% or less of the diol structural units being units derived from a diol having a cyclic acetal skeleton, and 70-98 mol% of the diol structural units being units derived from a diol having an alicyclic skeleton, the diol constitutional units include units derived from ethylene glycol, 80 mol% or more of the dicarboxylic acid constitutional units are units derived from terephthalic acid, and the polyester resin has the physical properties represented by (A) below. (A) The minimum value of the half-crystallization time measured by a depolarization intensity method when melting is performed at 280 DEG C and isothermal crystallization is performed at 150-230 DEG C is 600 seconds or less.

The invention discloses a method for controlling the crystallization of α-olefin homopolymer through processing conditions, and belongs to the technical field of polymer crystallization. The long-chain α-olefin homopolymer with 12-20 carbon atoms is heated to 160°C and kept for 10 minutes, and the temperature is lowered so that the long-chain α-olefin homopolymer crystallizes to obtain the initial sample; then the temperature is raised to 45-160°C to melt and Keep warm for 1-3600s, then cool down to an isothermal temperature of 10-75°C at 10°C / min; apply a shear strain rate of 0-5s ‑1 , a flow field with a shear time of 0‑5s, and crystallization at the isothermal crystallization temperature. In the present invention, there are obvious differences in the crystallization time of long-chain α-olefin homopolymers under different processing conditions, which shows that processing conditions have a greater impact on the crystallization time of long-chain α-olefin homopolymers, and provides a basis for improving processing and molding efficiency. a feasible solution.

The invention belongs to the technical field of high polymer materials, and particularly relates to a crystallization regulation and control method of star-shaped polycaprolactone, a polycaprolactone film and application of the polycaprolactone film. The crystallization regulation and control method comprises the following steps: dissolving star-shaped polycaprolactone in toluene to obtain a film forming solution; carrying out melting heat treatment on the film-forming liquid after film formation, and then transferring to a crystallization temperature environment for isothermal crystallization; wherein the formation and growth rate of the polycaprolactone girdle spherocrystals is regulated and controlled by changing the arm number, crystallization temperature and formed film thickness of the star-shaped polycaprolactone. According to the invention, polycaprolactone with a star-shaped topological structure is used, the formation of the annulus spherocrystal, the bandwidth of the annulus spherocrystal and the growth rate of the annulus spherocrystal can be regulated and controlled by changing the arm number, the crystallization temperature and the film thickness, the method is simple, other substances do not need to be added, the preparation conditions are mild and controllable, the operation is convenient, and the method is suitable for industrial production. Pure polycaprolactone materials with different annulus spherocrystal bandwidths and growth rates can be obtained, and application of the pure polycaprolactone materials as special optical materials becomes possible.

The invention discloses a preparation method of a disposable polylactic acid high temperature resistant cup cover. The cup cover comprises following components in parts by weight: 73.8 to 86.5 parts of PLLA, 5 to 10 parts of PGA, 8 to 15 parts of talcum powder, 0.1 to 0.6 part of aluminum-titanium coupling agent, and 0.4 to 0.6 part of food grade white oil. The preparation method comprises following steps: adding talcum powder with a predetermined weight into a high speed stirring machine, then adding an aluminum-titanium coupling agent; then sequentially adding prepared PLLA, PGA, and food grade white oil into the high speed stirring machine; adding the mixture into a double screw extruder with a length / diameter ratio of 48;1, carrying out extruding, stretching, cooling, and slicing to obtain PLLA modified resin particles; adding PLLA modified resin particles into a single screw extruder with a length / diameter ratio of 44:1, carrying out extruding and sheeting to obtain PLLA sheets; heating and baking obtained PLLA sheets by a positive-negative pressure plastic thermo-forming machine, and then carrying out isothermal crystallization, moulding, punching, and cutting to obtain the PLLA heatproof disposable hot-drink cup cover. PGA and PLLA are blended together, the phenomenon that other micromolecular nucleating agents are easily volatilized or precipitated out is avoided, and the application safety is largely improved.

The invention provides a fat composition for filling or sauce, the fat composition optionally contains an emulsifier, and has the following characteristics: (1) solid fat content ≥ 8% at 10°C; (2) solid fat content at 20°C Fat content ≥ 2%; and (3) Solid fat content ≥ 2% during isothermal crystallization at 10°C for 4 minutes. The oil composition of the present invention has the characteristics of low saturation, the sauce made from the composition is relatively stable, and is not easy to leak oil at high temperature, and can be used in baked products such as bread, cookies and cakes, and is resistant to baking, and the sandwich is not easy to dry out .

The present invention discloses a method for predicting the morphology of spherulites after crystallization based on DSC test results, comprising selecting representative cubic volume units, uniformly dividing the cubic unit grid into pixel point types, establishing a three-dimensional isothermal crystallization process crystal growth model of a semi-crystalline resin using a cellular automaton method, and inputting multiple sets of different parameters G and I based on the model to obtain the corresponding spherulite semi-crystallization time t. 0.5 The parameter ln(k) and the characteristic parameter t in the Avrami model of crystallization kinetics c The functional relationship between them is used to construct the average radius of the spherulites based on the multiple sets of different parameters G and I input above. <r>The functional relationship between the characteristic parameter Lc and the spherulite morphology after crystallization of semi-crystalline resin can be obtained by performing a simple DSC test on the material. 0.5 and the value of ln(k), the spherulite morphology after crystallization can be directly predicted through the obtained functional relationship, thus reducing the experimental time.< / r>

The invention relates to a polymer composition for container closures. The present invention relates to a polymer composition comprising an ethylene homopolymer and an ethylene copolymer having a comonomer content comprising a comonomer in an amount of at least 0.55 mol% with respect to the total amount of monomer in the ethylene copolymer, wherein the ethylene copolymer has a higher weight average molecular weight than the ethylene homopolymer, the polymer composition has a density in the range of 0.950-0.965 g / cm<3> , a melt flow rate (MFR2) of at least 0.3 g / 10 minutes, a weight average molecular weight of at least 100,000 g / mol, and a viscosity eta 0.01 at an angular frequency of 0.01 [1 / s] of at least 20,000 Pa.s, wherein the polymer composition has an isothermal crystallization half-time ICHT which is less than 10 minute at 123 DEG C and a full notch creep test FNCT of at least 60 hours.

The invention provides a mixed matrix membrane with an organic metal framework continuous passage as well as a preparation method and application of the mixed matrix membrane, and belongs to the field of high polymer materials and gas separation membranes. The mixed matrix membrane is composed of a highly continuous organometallic framework and an amorphous polyoxyethylene body. The invention also provides a preparation method of the mixed matrix membrane with the organic metal framework continuous passage. Polyethylene oxide has the characteristic of easy crystallization, in the isothermal crystallization process, a nanoscale organic metal framework, polyethylene glycol diacrylate and a photoinitiator can be discharged to an amorphous region of the organic metal framework, a highly continuous organic metal framework channel is formed, and then photo-crosslinking treatment is carried out to form a crosslinked amorphous network, so that the organic metal framework and the polyethylene glycol diacrylate are subjected to heat treatment to form an organic metal framework. And the crystallinity of polyoxyethylene is reduced while a continuous organic metal framework channel is fixed, so that the amorphous state is kept after high-temperature quenching.

The invention discloses a high-strength and high-barrier polylactic acid film and a preparation method and application thereof.The preparation method comprises the following steps that S1, a polylactic acid matrix and block copolymerized polylactic acid are dissolved with a solvent and then mixed, and a solution is obtained; s2, precipitating the solution with ethanol to obtain a precipitate; s3, the precipitate is dried, and a blend is obtained; and S4, carrying out melting, hot pressing and isothermal crystallization on the blend to obtain the high-strength and high-barrier polylactic acid film. Block copolymerized polylactic acid is utilized to promote rapid crystallization of a polylactic acid matrix, and the polylactic acid film is endowed with high barrier property while the mechanical property of the polylactic acid film is improved. The prepared high-strength and high-barrier polylactic acid film is applied to the field of packaging or agricultural mulching films.