WO2020134498A1 - 可降解的聚酯纤维及其制备方法 - Google Patents

可降解的聚酯纤维及其制备方法 Download PDF

Info

Publication number
WO2020134498A1
WO2020134498A1 PCT/CN2019/113873 CN2019113873W WO2020134498A1 WO 2020134498 A1 WO2020134498 A1 WO 2020134498A1 CN 2019113873 W CN2019113873 W CN 2019113873W WO 2020134498 A1 WO2020134498 A1 WO 2020134498A1
Authority
WO
WIPO (PCT)
Prior art keywords
reaction
acid
heptanediol
temperature
tetramethyl
Prior art date
Application number
PCT/CN2019/113873
Other languages
English (en)
French (fr)
Inventor
张元华
丁竹君
王丽丽
Original Assignee
江苏恒力化纤股份有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 江苏恒力化纤股份有限公司 filed Critical 江苏恒力化纤股份有限公司
Priority to US17/277,306 priority Critical patent/US11174345B2/en
Priority to JP2021533240A priority patent/JP7053960B2/ja
Priority to EP19905717.5A priority patent/EP3842577B1/en
Publication of WO2020134498A1 publication Critical patent/WO2020134498A1/zh

Links

Classifications

    • D—TEXTILES; PAPER
    • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
    • D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
    • D01F6/00—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof
    • D01F6/78—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from copolycondensation products
    • D01F6/84—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from copolycondensation products from copolyesters
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
    • C08G63/68—Polyesters containing atoms other than carbon, hydrogen and oxygen
    • C08G63/682—Polyesters containing atoms other than carbon, hydrogen and oxygen containing halogens
    • C08G63/6824—Polyesters containing atoms other than carbon, hydrogen and oxygen containing halogens derived from polycarboxylic acids and polyhydroxy compounds
    • C08G63/6826—Dicarboxylic acids and dihydroxy compounds
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
    • C08G63/02—Polyesters derived from hydroxycarboxylic acids or from polycarboxylic acids and polyhydroxy compounds
    • C08G63/12—Polyesters derived from hydroxycarboxylic acids or from polycarboxylic acids and polyhydroxy compounds derived from polycarboxylic acids and polyhydroxy compounds
    • C08G63/16—Dicarboxylic acids and dihydroxy compounds
    • C08G63/18—Dicarboxylic acids and dihydroxy compounds the acids or hydroxy compounds containing carbocyclic rings
    • C08G63/181—Acids containing aromatic rings
    • C08G63/183—Terephthalic acids
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
    • C08G63/78—Preparation processes
    • C08G63/82—Preparation processes characterised by the catalyst used
    • C08G63/85—Germanium, tin, lead, arsenic, antimony, bismuth, titanium, zirconium, hafnium, vanadium, niobium, tantalum, or compounds thereof
    • C08G63/86—Germanium, antimony, or compounds thereof
    • C08G63/866—Antimony or compounds thereof
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K9/00—Use of pretreated ingredients
    • C08K9/02—Ingredients treated with inorganic substances
    • D—TEXTILES; PAPER
    • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
    • D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
    • D01F1/00—General methods for the manufacture of artificial filaments or the like
    • D01F1/02—Addition of substances to the spinning solution or to the melt
    • D01F1/10—Other agents for modifying properties
    • D—TEXTILES; PAPER
    • D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
    • D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
    • D01F6/00—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof
    • D01F6/88—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from mixtures of polycondensation products as major constituent with other polymers or low-molecular-weight compounds
    • D01F6/92—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from mixtures of polycondensation products as major constituent with other polymers or low-molecular-weight compounds of polyesters
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
    • C08K3/20—Oxides; Hydroxides
    • C08K3/22—Oxides; Hydroxides of metals
    • C08K2003/2244—Oxides; Hydroxides of metals of zirconium

Definitions

  • the invention belongs to the technical field of polyester fibers, and relates to a degradable polyester fiber and a preparation method thereof.
  • Polyester fiber is the first large variety of synthetic fiber. It is made from purified terephthalic acid (PTA) or dimethyl terephthalate (DMT) and ethylene glycol (EG) as raw materials through esterification or transesterification.
  • PTA purified terephthalic acid
  • DMT dimethyl terephthalate
  • EG ethylene glycol
  • PET Polyethylene terephthalate
  • PET a fiber-forming polymer obtained by polycondensation reaction, is produced by spinning and post-treatment.
  • As a semi-crystalline high molecular polymer with good thermoplasticity it is widely used in various fields such as taking, packaging, biology, production and processing.
  • PET waste has become a global environmentally polluting organic substance .
  • the vast majority of ultra-fine denier fibers are used in the apparel field.
  • the amount of waste clothing has also increased year by year, and nearly 30 million tons of waste clothing is generated in my country every year.
  • the common disposal methods for PET waste are landfill, incineration and recycling. Although landfill and incineration are the simplest methods, they will also cause certain pollution to the environment.
  • chemical degradation methods are mostly used for the degradation of PET.
  • the chemical decomposition methods mainly include hydrolysis and alcoholysis, in addition to ammonia hydrolysis, amine hydrolysis and pyrolysis.
  • the chemical degradation method currently used still has the problems of slow degradation rate and poor degradation effect, and it still cannot solve the degradation and recycling of a large number of waste clothing.
  • polyester fiber polyester filament
  • the purpose of the present invention is the defect of the slow degradation rate in the prior art, providing a polyester fiber with a fast natural degradation rate and a preparation method thereof.
  • the preparation method of the degradable polyester fiber is to obtain the modified polyester FDY yarn from the modified polyester melt system according to the FDY process, that is, the degradable polyester fiber is obtained;
  • the preparation method of the modified polyester is: changing terephthalic acid, ethylene glycol, 2,5,6,6-tetramethyl-2,5-heptanediol, fluorine-containing dibasic acid and doping
  • the ZrO 2 powder is mixed evenly and then esterified and then polycondensed.
  • Fluorine-containing dibasic acid is 2,2-difluoro-1,3-malonic acid, 2,2-difluoro-1,4-succinic acid, 2,2-difluoro-1,5-glutaric acid Or 2,2,3,3-tetrafluoro-1,4-succinic acid;
  • the process of ZrO 2 doping modification is as follows: firstly, the solution containing the metal ion M x+ and the solution containing Zr 4+ are mixed evenly, then the precipitant is added dropwise until the pH of the mixed solution is 9-10, and finally the calcined precipitated product;
  • the metal ion M x+ is at least one of Mg 2+ , Li + and Zn 2+ .
  • the invention uses 2,5,6,6-tetramethyl-2,5-heptanediol to modify polyester, and 2,5,6,6-tetramethyl-2,5-heptanediol can significantly Increase the space free volume of modified polyester, especially the presence of tert-butyl group in 2,5,6,6-tetramethyl-2,5-heptanediol will cause changes in the activity of the main chain, thus changing The interaction force between the chain units and the distance between the molecular chain units will also change accordingly, increasing the free volume of the modified polyester voids.
  • the free volume of the cavity is more conducive to the diffusion of molecules such as air and water into the fiber, which can reduce the difficulty of the penetration of molecules such as air and water into the modified polyester and improve the natural degradation of the modified polyester to a certain extent. performance.
  • the invention further improves the natural degradation performance of the modified polyester by adding fluorine-containing dibasic acid and doped modified ZrO 2 powder;
  • the special feature of the fluorine-containing dibasic acid of the present invention is that the fluorine atom is on the alpha carbon.
  • the fluorine-containing dibasic acid is introduced in the hydrolysis process, since the fluorine atom is on the alpha carbon, the electron-withdrawing ability is strong, making the poly The electron cloud density on the CO bond in the ester is reduced, and the stability of the tetrahedral anions is reduced, which is conducive to the nucleophilic addition reaction.
  • the steric hindrance of the fluorine-containing dibasic acid on the ⁇ carbon is less than that of terephthalic acid. It further promotes the progress of nucleophilic addition reaction, thus significantly increasing the degradation rate.
  • the invention realizes the doping of metal oxides (more than one of magnesium oxide, lithium oxide and zinc oxide) and ZrO 2 through the method of solution blending, co-precipitation and calcination, and then the catalytic process of oxygen reduction of ZrO 2 It has an impact and increases the degradation rate of polyester. Since ZrO 2 with high ion conductivity is used as the substrate of the oxygen reduction catalyst in the present invention, it can obtain a stable cubic phase by doping with low-valence metal ions (Mg 2+ , Li + and Zn 2+ ). To a certain extent, the closer the doped ion radius is to the doped ion radius, the more conducive to the formation of oxygen vacancies and the more conducive to the conduction of oxygen ions.
  • metal ions (Mg) with the same radius as the Zr 4+ ion are selectively doped 2+ , Li + and Zn 2+ , all of which have an ion radius of 0.103 nm), which can increase the conduction rate of oxygen ions, thereby increasing the degree of oxygen reduction reaction.
  • the 2,5,6,6-tetramethyl-2,5-heptanediol, fluorine-containing dibasic acid and doped modified ZrO 2 powder introduced in the present invention can also play a synergistic role, fluorine-containing binary
  • the acid reduces the density of the electron cloud on the CO bond, promotes the nucleophilic addition reaction, and is beneficial to the degradation reaction.
  • the doped and modified ZrO 2 powder increases the conduction rate of oxygen ions, thereby increasing the degree of oxygen reduction reaction.
  • 2,5,6,6-tetramethyl-2,5-heptanediol increases the void free volume of the polyester, which is conducive to the penetration of oxygen and water, and improves the internal oxygen of the polyester
  • concentration of atoms, the combination of the three significantly increases the degradation rate.
  • the metal ion M x + in the solution is 1 ⁇ 2wt%
  • the solvent is water
  • the solution of + is a solution of ZrO 2 with a concentration of 20 to 25% by weight, and the solvent is nitric acid
  • the precipitant is ammonia with a concentration of 2 mol/L
  • the molar ratio of metal ions M x+ to Zr 4+ in the mixed solution is 5 ⁇ 8:100
  • the molar ratio of the metal ion M x+ to Zr 4+ in the present invention is not limited to this, those skilled in the art can adjust it according to the actual situation, but the adjustment range should not be too large, because ZrO 2 in the catalyst is
  • the main body, the introduction of metal ions M x+ is developed around ZrO 2 , the purpose is to increase the conduction rate of oxygen ions, and thereby increase the degree of oxygen reduction reaction.
  • the precipitated product is washed and dried before the calcination, the drying temperature is 105 ⁇ 110°C, and the time is 2 ⁇ 3h; the process of the calcination is: first warm up to 400°C, then keep it warm for 2 ⁇ 3h, and then raise the temperature to 700°C After heat preservation for 1 ⁇ 2h, and finally cooling in air; ZrO 2 is crushed after doping modification to obtain powder with an average particle size of less than 0.5 microns.
  • the preparation steps of the modified polyester are as follows:
  • esterification reaction is carried out under pressure in a nitrogen atmosphere.
  • the pressure is from normal pressure to 0.3 MPa.
  • the temperature of the esterification reaction is 250 to 260°C.
  • the polycondensation reaction in the low-vacuum stage is started under negative pressure.
  • the pressure in this stage is steadily pumped from normal pressure to an absolute pressure of 500 Pa or less within 30 to 50 minutes.
  • the reaction temperature is 250 to 260°C and the reaction time is 30 ⁇ 50min, and then continue to evacuate to carry out the polycondensation reaction in the high vacuum stage to further reduce the reaction pressure to below 100Pa absolute pressure, the reaction temperature is 270 ⁇ 282°C, and the reaction time is 50 ⁇ 90min.
  • the molar ratio of terephthalic acid to ethylene glycol is 1:1.2 ⁇ 2.0, and the 2,5,6,6-tetramethyl-2 ,5-heptanediol and fluorine-containing dibasic acid are added in an amount of 4 to 6 mol% of the addition amount of terephthalic acid.
  • the 2,5,6,6-tetramethyl-2,5-heptanediol The molar ratio with the fluorine-containing dibasic acid is 1 ⁇ 2:1 ⁇ 2, and the addition amount of the doped modified ZrO 2 powder, catalyst, matting agent and stabilizer is 0.23 of the addition amount of terephthalic acid, respectively ⁇ 0.25wt%, 0.03 ⁇ 0.05wt%, 0.20 ⁇ 0.25wt% and 0.01 ⁇ 0.05wt%.
  • 2,5,6,6-Tetramethyl-2,5-heptanediol is added in an excessive amount (such as greater than 0.1), the regularity of the polyester macromolecular structure is destroyed too much, and the crystallinity and mechanics of the fiber Too much influence on performance (rigidity) is not conducive to the production and application of fibers; if the addition amount is too small (such as less than 0.01), the increase in the void free volume of polyester is not obvious, and it is difficult to significantly improve the natural degradation performance of polyester.
  • the addition amount of the doped and modified ZrO 2 powder of the present invention is not limited to this, and those skilled in the art can adjust it according to the actual situation, but the adjustment range should not be too large.
  • the addition amount of the fluorine-containing dibasic acid of the present invention is not limited to this, and those skilled in the art can adjust it according to the actual situation, but the adjustment range should not be too large. If the addition amount is too large, the regularity of the polyester macromolecular structure is destroyed too much. Too much influence on the crystallinity and mechanical properties of the fiber is not conducive to the production and application of the fiber. If the amount is too low, the effect (improvement of natural degradation performance) is not obvious.
  • the catalyst is antimony trioxide, ethylene glycol antimony or antimony acetate
  • the matting agent is titanium dioxide
  • the stabilizer is triphenyl phosphate and phosphoric acid Trimethyl or trimethyl phosphite.
  • the modified polyester has a number average molecular weight of 25,000 to 30,000 and a molecular weight distribution index of 1.8 to 2.2.
  • the preparation method of the degradable polyester fiber as described above, the flow of the FDY process is: metering, spinneret extrusion, cooling, oiling, drawing, heat setting and winding;
  • the parameters of the FDY process are: spinning temperature 285 to 295°C, cooling temperature 19 to 22°C, network pressure 0.20 to 0.30MPa, speed of one roller 2300 to 2700 m/min, temperature of one roller 80 to 90°C, speed of two rollers 3800 ⁇ 4200m/min, two-roller temperature 115 ⁇ 130°C, winding speed 3730 ⁇ 4120m/min.
  • the specific parameters of the FDY process of the present invention are not limited to this, only one feasible process parameter is given here.
  • the present invention also provides a degradable polyester fiber prepared by the preparation method of the degradable polyester fiber as described above, which is a modified polyester FDY yarn;
  • the molecular chain of the modified polyester includes terephthalic acid segment, ethylene glycol segment, 2,5,6,6-tetramethyl-2,5-heptanediol segment and fluorine-containing dibasic acid Chain segment
  • the modified polyester is dispersed with doped modified ZrO 2 powder; the process of doping modification is: firstly mix the solution containing metal ions M x+ and the solution containing Zr 4+ uniformly, then add the precipitation dropwise
  • the pH value of the agent to the mixed solution is 9-10, and finally the precipitated product is calcined; the metal ion M x+ is more than one of Mg 2+ , Li + and Zn 2+ .
  • the degradable polyester fiber has a monofilament fineness of 1.0 to 2.0 dtex, a breaking strength ⁇ 3.0 cN/dtex, an elongation at break of 32.0 ⁇ 4.0%, and a network degree of 13 ⁇ 2 pcs/m, linear density deviation rate ⁇ 1.0%, breaking strength CV value ⁇ 5.0%, breaking elongation CV value ⁇ 9.0%, boiling water shrinkage rate 6.5 ⁇ 0.5%, 2,5,6,6- of the present invention
  • the addition amount of tetramethyl-2,5-heptanediol, fluorine-containing dibasic acid and doped modified ZrO 2 powder is small, and its influence on the processing and mechanical properties of polyester fiber is small, the invention
  • the processing performance and mechanical properties of the degradable polyester fiber are the same as those of ordinary polyester fiber (without adding 2,5,6,6-tetramethyl-2,5-heptanediol, fluorine-containing dibasic acid and doping Sexual ZrO 2 powder) is equivalent;
  • the degradable polyester fiber After the degradable polyester fiber was placed under the conditions of 25°C and 65% relative humidity for 60 months, its intrinsic viscosity decreased by 23 to 28%; under the same conditions, the intrinsic viscosity of the comparative sample decreased by 4.3%.
  • the difference from the modified polyester FDY yarn of the present invention is only that its material is ordinary polyester and no doped modified ZrO 2 powder is added, and the degradable polyester fiber of the present invention is naturally degraded compared to conventional PET fiber The rate increases significantly. 2,5,6,6-tetramethyl-2,5-heptanediol, fluorine-containing dibasic acid and doped modified ZrO 2 powder can significantly increase the fiber's natural degradation rate.
  • the macromolecular chains in the polymer are not completely tightly packed, there are always gaps between the macromolecular chains, and the volume of this part of the void is the free volume.
  • the permeability and diffusivity of the small molecule are related to the size of the void (ie, the size of the free volume) in the polymer structure.
  • the larger the size of the free volume the higher the permeability of small molecules and the better the diffusibility.
  • Free volume is divided into cavity free volume and slit free volume.
  • the cavity free body has a larger space size than the slit free volume.
  • the cavity free volume is more obvious than the slit free volume.
  • the size and type of free volume mainly depend on the structure of the polymer.
  • the main factors affecting the structure of the polymer are steric hindrance, side group size, side group structure, etc.
  • When a position on the polymer main chain is substituted with a pendant group it will inevitably cause changes in the main chain activity, thereby changing the interaction force between chains, and the distance between chains will also change accordingly. This leads to changes in cohesive energy and free volume.
  • the polarity, size, and length of the substituents on the side chain of the polymer have certain effects on the rigidity of the molecular chain, the interaction between molecules, and the free volume fraction of the polymer structure. Therefore, different substituents have different effects, which often lead to different permeation and separation properties of polymers.
  • the C atoms in the main chain are arranged in a zigzag pattern, when the two H atoms on a methylene group in the main chain are methyl (- CH 3 ) substitution, the C atoms on these two side groups are not in the same plane as the C atoms of the main chain, so the four sp3 hybrid orbitals on the center C overlap the empty orbitals on the surrounding four C atoms, Four identical ⁇ bonds are formed, arranged in a regular tetrahedron. The four carbon atoms are located at the four vertices of the regular tetrahedron.
  • the molecular chain of the regular tetrahedron has a much larger free volume of voids, which can significantly improve the permeability and diffusivity of small molecules.
  • the main increase is the free volume of the slit, the increase is smaller, the permeability and diffusivity of small molecules The lifting effect is limited.
  • the molecular chains are prone to entanglement, which is not conducive to the increase of free volume.
  • the invention significantly improves the natural degradation performance of the polyester fiber by introducing 2,5,6,6-tetramethyl-2,5-heptanediol into the polyester molecular chain.
  • 2,5,6,6-tetramethyl The structural formula of yl-2,5-heptanediol is as follows:
  • tert-butyl occupies a larger space position, and will obtain a larger free volume in the manner of molecular chain arrangement;
  • tertiary butyl increases the void free volume, while long-chain branched substituents increase the slit free volume, on the other hand, tertiary butyl is more rigid than long-chain branched substituents, reducing The entanglement between the molecular chains, so the longer-branched tertiary butyl substituent has more free volume in the way the molecular chains are arranged.
  • the free volume of the cavity is better than the increase of the free volume of the slit.
  • the present invention increases the free volume of the cavity to make it easier for water or other molecules such as air to penetrate
  • the interior of the polyester macromolecules has a positive effect on the natural degradation properties of the modified polyester.
  • the hydrolysis and degradation of polyester under alkaline conditions is a nucleophilic addition-elimination process.
  • OH - attacks the C atom of the ester carbonyl RCOOR ⁇
  • a nucleophilic addition reaction occurs, forming an intermediate (ie, four-sided Negative ion of the tetrahedron)
  • the negative ion of the tetrahedron can eliminate OR ⁇ to obtain carboxylic acid RCOOH, break the ester bond, and at the same time OR ⁇ combines with H + to obtain alcohol HOR ⁇ .
  • the tetrahedral negative ion structure formed during the hydrolysis process is crowded and steric hindrance is large, which is not conducive to the nucleophilic addition reaction, so the degradation rate of polyester is slow.
  • the invention significantly improves the degradation rate of polyester by introducing a fluorine-containing dibasic acid with a special structure into the polyester molecular chain.
  • the special feature of the fluorine-containing dibasic acid is that the fluorine atom is on the alpha carbon, which is introduced during the hydrolysis process.
  • the electron withdrawing ability is strong, so that the electron cloud density on the CO bond in the polyester is reduced, and the stability of the tetrahedral negative ion is reduced, which is beneficial to nucleophilic addition.
  • the steric hindrance of the fluorinated dibasic acid on the ⁇ carbon is smaller than that of terephthalic acid, which further promotes the nucleophilic addition reaction, thus significantly increasing the degradation rate.
  • the fluorine-containing dibasic acid with a fluorine atom in the ⁇ carbon is introduced into the polyester molecular chain, the degradation rate of the polyester will not be significantly increased, because the presence of electron withdrawing groups on the ⁇ carbon only affects It is limited to the adjacent carbon and has little effect on the CO bond in the ester bond, so it has little effect on the nucleophilic addition reaction of the OH - attack ester carbonyl group.
  • the oxygen in the air can penetrate into the polyester through the free volume (narrow free volume and/or void free volume) in the polyester material Inside, the surface of the oxygen reduction catalyst adsorbs oxygen, and the oxygen gradually migrates to the surface of the oxygen reduction catalyst inside the polyester. After reaching a certain oxygen concentration gradient, the adsorbed oxygen is formed, and an oxygen reduction reaction (oxygen ionization) occurs on the surface of the oxygen reduction catalyst. During the reaction, oxygen is partially reduced to peroxide.
  • the oxygen molecules adsorbed by the oxygen reduction catalyst are combined with an ester bond in a polyester and form RCOOOR ⁇ on the catalyst surface, and then a proton is combined to break the oxygen-oxygen bond.
  • An RCOOH is formed, which breaks the ester bond, and at the same time OR ⁇ combines with H + to obtain an alcohol HOR ⁇ , thereby accelerating the degradation of polyester.
  • the invention realizes the doping of metal oxides (more than one of magnesium oxide, lithium oxide and zinc oxide) and ZrO 2 through the method of solution blending, co-precipitation and calcination, and then the catalytic process of oxygen reduction of ZrO 2 It has an impact and increases the degradation rate of polyester. Since ZrO 2 with high ion conductivity is used as the substrate of the oxygen reduction catalyst in the present invention, it can obtain a stable cubic phase by doping with low-valence metal ions (Mg 2+ , Li + and Zn 2+ ). To a certain extent, the closer the doped ion radius is to the doped ion radius, the more conducive to the formation of oxygen vacancies and the more conducive to the conduction of oxygen ions.
  • metal ions (Mg) with the same radius as the Zr 4+ ion are selectively doped 2+ , Li + and Zn 2+ , all of which have an ion radius of 0.103 nm), which can increase the conduction rate of oxygen ions, thereby increasing the degree of oxygen reduction reaction.
  • the effect of doping on ZrO 2 is as follows:
  • the doping method of the present invention can destroy the crystal plane structure of ZrO 2 and increase its specific surface area, thereby increasing the oxygen adsorption capacity per unit mass of ZrO 2 ;
  • the doping method of the present invention can change the adsorption method of ZrO 2 and the oxygen reduction reaction mechanism.
  • the adsorption method is the end-type adsorption on the surface of monoclinic ZrO 2.
  • O atoms are in different monoclinic ZrO When the 2 crystal plane is adsorbed, it will be affected by the "steric hindrance effect" of the Zr atoms on the surface.
  • the O 2 molecule is adsorbed on the Zr atom site by weaker physical adsorption or weak chemical adsorption, and the O is on a different monoclinic ZrO 2 crystal plane.
  • the 2,5,6,6-tetramethyl-2,5-heptanediol, fluorine-containing dibasic acid and doped modified ZrO 2 powder introduced in the present invention can also play a synergistic role, fluorine-containing binary
  • the acid reduces the density of the electron cloud on the CO bond, promotes the nucleophilic addition reaction, and is beneficial to the degradation reaction.
  • the doped and modified ZrO 2 powder increases the conduction rate of oxygen ions, thereby increasing the degree of oxygen reduction reaction.
  • 2,5,6,6-tetramethyl-2,5-heptanediol increases the void free volume of the polyester, which is conducive to the penetration of oxygen and water, and improves the internal oxygen of the polyester
  • concentration of atoms, the combination of the three significantly increases the degradation rate.
  • the preparation method of the degradable polyester fiber of the present invention is increased by introducing a modified component in the polyester—belt 2,5,6,6-tetramethyl-2,5-heptanediol
  • the free volume of the void increases the natural degradation rate to a certain extent
  • the preparation method of the degradable polyester fiber of the present invention significantly improves the naturalness of the polyester fiber by introducing components-fluorine-containing dibasic acid and doped modified ZrO 2 powder into the polyester Degradation rate
  • the degradable polyester fiber of the present invention has a rapid natural degradation rate, good mechanical properties, and broad application prospects.
  • a preparation method of degradable polyester fiber the steps are as follows:
  • Terephthalic acid ethylene glycol, 2,5,6,6-tetramethyl-2,5-heptanediol and 2,2-difluoro-1,3-malonic acid are mixed into a slurry, and doping is added After the modified ZrO 2 powder, antimony trioxide, titanium dioxide and triphenyl phosphate are mixed evenly, the esterification reaction is carried out under pressure in a nitrogen atmosphere. The pressure is 0.3 MPa and the temperature of the esterification reaction is 250°C.
  • the molar ratio of terephthalic acid to ethylene glycol is 1:1.5, 2,5,6,6-tetramethyl -The sum of the addition of 2,5-heptanediol and 2,2-difluoro-1,3-malonic acid is 6mol% of the addition of terephthalic acid, 2,5,6,6-tetramethyl- 2,5-heptanediol and 2,2-difluoro-1,3-malonic acid molar ratio is 1:1, doped with modified ZrO 2 powder, antimony trioxide, titanium dioxide and triphenyl phosphate The added amounts are 0.25%, 0.05%, 2.0% and 0.01% by weight of terephthalic acid respectively;
  • the polycondensation reaction in the low-vacuum stage is started under negative pressure.
  • the pressure in this stage is steadily pumped from normal pressure to absolute pressure of 499 Pa within 30 minutes, the reaction temperature is 250 °C, the reaction time is 30 minutes, and then continue to vacuum Carry out the polycondensation reaction in the high vacuum stage to further reduce the reaction pressure to 99Pa absolute pressure, the reaction temperature is 270°C, the reaction time is 50min, and a modified polyester with a number average molecular weight of 25,000 and a molecular weight distribution index of 1.8 is prepared;
  • Modified polyester FDY yarns are obtained after the polyester melt is metered, spinneret extruded, cooled, oiled, drawn, heat set and wound, that is, degradable polyester fibers are obtained.
  • the parameters of the FDY process are : Spinning temperature 290°C, cooling temperature 20°C, network pressure 0.25MPa, one-roller speed 2500m/min, one-roller temperature 85°C, second-roller speed 4000m/min, second-roller temperature 120°C, winding speed 4000m/min.
  • the monofilament fineness of the degradable polyester fiber is 1.5dtex, the breaking strength is 3.0cN/dtex, the elongation at break is 28%, the network degree is 11 pieces/m, the linear density deviation rate is 1.0%, the breaking strength CV value It is 4.8%, the breaking elongation CV value is 8.7%, and the boiling water shrinkage is 7.0%;
  • a method for preparing polyester fiber is basically the same as that in Example 1, except that step (1.3) does not add 2,5,6,6-tetramethyl-2,5-heptanediol, 2, 2-Difluoro-1,3-malonic acid and doped modified ZrO 2 powder.
  • the monofilament fineness of the polyester fiber finally obtained was 1.5 dtex, the breaking strength was 3.1 cN/dtex, the elongation at break was 27%, the network degree was 11 pieces/m, the linear density deviation rate was 1.0%, and the breaking strength was CV The value is 5.0%, the breaking elongation CV value is 8.7%, and the boiling water shrinkage is 7.0%;
  • a method for preparing polyester fiber is basically the same as that in Example 1, except that in step (1.3), 3,3-difluoroglutaric acid is used instead of 2,2-difluoro-1,3-propanedi Acid, the resulting polyester fiber was placed at 25°C and 65% relative humidity for 60 months, and its intrinsic viscosity decreased by 14.8%.
  • Comparing Example 1 with Comparative Example 1 shows that due to fluorine ⁇ carbon atoms in the presence of a fluorine-containing ⁇ carbon dibasic acid electron withdrawing group, the impact is limited to adjacent carbon, and the effect on CO bond ester bond produced small, and thus for OH -
  • the nucleophilic addition reaction of the attacking ester carbonyl group has little effect, and thus has little effect on the natural degradation process of the fiber. Therefore, the fluorine-containing dibasic acid of the fluorine atom of the present invention in the alpha carbon is more conducive to doping modified ZrO 2
  • the powder acts synergistically to improve the natural degradation of the fiber.
  • a preparation method of degradable polyester fiber the steps are as follows:
  • Terephthalic acid ethylene glycol, 2,5,6,6-tetramethyl-2,5-heptanediol and 2,2-difluoro-1,4-succinic acid are mixed into a slurry, and doping is added After the modified ZrO 2 powder, ethylene glycol antimony, titanium dioxide and trimethyl phosphate are mixed evenly, the esterification reaction is carried out under pressure in a nitrogen atmosphere, the pressure is normal pressure, and the temperature of the esterification reaction is 260°C.
  • the molar ratio of terephthalic acid and ethylene glycol is 1:1.2, 2,5,6,6-tetramethyl -The sum of the addition of 2,5-heptanediol and 2,2-difluoro-1,4-succinic acid is 4mol% of the addition of terephthalic acid, 2,5,6,6-tetramethyl-
  • the molar ratio of 2,5-heptanediol and 2,2-difluoro-1,4-succinic acid is 2:2, doped with modified ZrO 2 powder, ethylene glycol antimony, titanium dioxide and trimethyl phosphate
  • the added amounts are 0.23wt%, 0.05wt%, 2.2wt% and 0.05wt% of terephthalic acid respectively;
  • the polycondensation reaction in the low-vacuum stage is started under negative pressure.
  • the pressure in this stage is steadily pumped from normal pressure to an absolute pressure of 450 Pa within 50 minutes, the reaction temperature is 260 °C, the reaction time is 50 minutes, and then continue to vacuum Carry out the polycondensation reaction in the high vacuum stage to further reduce the reaction pressure to 90Pa absolute pressure, the reaction temperature is 282°C, the reaction time is 90min, and a modified polyester with a number average molecular weight of 30,000 and a molecular weight distribution index of 2.2 is prepared;
  • Modified polyester FDY yarns are obtained after the polyester melt is metered, spinneret extruded, cooled, oiled, drawn, heat set and wound, that is, degradable polyester fibers are obtained.
  • the parameters of the FDY process are : Spinning temperature 290°C, cooling temperature 20°C, network pressure 0.25MPa, one-roller speed 2500m/min, one-roller temperature 85°C, second-roller speed 4000m/min, second-roller temperature 120°C, winding speed 4000m/min.
  • the monofilament fineness of the degradable polyester fiber is 2.0 dtex, the breaking strength is 3.3 cN/dtex, the elongation at break is 36%, the network degree is 15 pcs/m, the linear density deviation rate is 0.8%, and the breaking strength CV value It is 4.2%, the breaking elongation CV value is 8.1%, and the boiling water shrinkage is 6.0%;
  • a preparation method of degradable polyester fiber the steps are as follows:
  • a concentration of 2wt% of Zn (NO 3) 2 solution with a concentration of 25wt% of ZrO 2 are uniformly mixed solution, a solvent solution of ZrO 2 as nitric acid, mixture of Zn 2+ and Zr 4+ molar The ratio is 8:100;
  • Terephthalic acid ethylene glycol, 2,5,6,6-tetramethyl-2,5-heptanediol and 2,2-difluoro-1,5-glutaric acid are mixed into a slurry, and doping is added
  • the esterification reaction is carried out under pressure in a nitrogen atmosphere. The pressure is 0.2 MPa and the temperature of the esterification reaction is 255°C.
  • the molar ratio of terephthalic acid to ethylene glycol is 1:1.5, 2,5,6,6-tetramethyl-
  • the sum of the added amounts of 2,5-heptanediol and 2,2-difluoro-1,5-glutaric acid is 4.4mol% of the added amount of terephthalic acid, 2,5,6,6-tetramethyl-
  • the molar ratio of 2,5-heptanediol and 2,2-difluoro-1,5-glutaric acid is 1:2, doped with modified ZrO 2 powder, antimony acetate, titanium dioxide and trimethyl phosphite
  • the added amounts are 0.23wt%, 0.05wt%, 2.3wt% and 0.01wt% of the added amount of terephthalic acid, respectively;
  • the polycondensation reaction in the low-vacuum stage starts under negative pressure.
  • the pressure in this stage is steadily pumped from normal pressure to 480 Pa absolute pressure within 40 minutes, the reaction temperature is 255 °C, the reaction time is 40 minutes, and then continue to vacuum Carry out the polycondensation reaction in the high vacuum stage to further reduce the reaction pressure to 95Pa absolute pressure, the reaction temperature is 272°C, the reaction time is 70min, and a modified polyester with a number average molecular weight of 27000 and a molecular weight distribution index of 2.0 is prepared;
  • Modified polyester FDY yarns are obtained after the polyester melt is metered, spinneret extruded, cooled, oiled, drawn, heat set and wound, that is, degradable polyester fibers are obtained.
  • the parameters of the FDY process are : Spinning temperature 290°C, cooling temperature 20°C, network pressure 0.25MPa, one-roller speed 2500m/min, one-roller temperature 85°C, second-roller speed 4000m/min, second-roller temperature 120°C, winding speed 4000m/min.
  • the monofilament fineness of the degradable polyester fiber is 1.0dtex, the breaking strength is 3.3cN/dtex, the elongation at break is 35%, the network degree is 14 pieces/m, the linear density deviation rate is 0.9%, the breaking strength CV value It is 4.3%, the breaking elongation CV value is 8.1%, and the boiling water shrinkage is 6.2%;
  • a preparation method of degradable polyester fiber the steps are as follows:
  • Terephthalic acid ethylene glycol, 2,5,6,6-tetramethyl-2,5-heptanediol and 2,2-difluoro-1,5-glutaric acid are mixed into a slurry, and doping is added After the modified ZrO 2 powder, ethylene glycol antimony, titanium dioxide and triphenyl phosphate are mixed evenly, the esterification reaction is carried out under pressure in a nitrogen atmosphere. The pressure is 0.25 MPa and the temperature of the esterification reaction is 250°C.
  • the molar ratio of terephthalic acid and ethylene glycol is 1:1.4, 2,5,6,6-tetramethyl -The sum of the added amount of -2,5-heptanediol and 2,2-difluoro-1,5-glutaric acid is 4.6mol% of the added amount of terephthalic acid, 2,5,6,6-tetramethyl -The molar ratio of -2,5-heptanediol and 2,2-difluoro-1,5-glutaric acid is 1.5:1, doped with modified ZrO 2 powder, ethylene glycol antimony, titanium dioxide and triphenyl phosphate
  • the added amount of ester is 0.24wt%, 0.07wt%, 3.0wt% and 0.01wt% of terephthalic acid respectively;
  • the polycondensation reaction in the low-vacuum stage starts under negative pressure.
  • the pressure in this stage is steadily pumped from normal pressure to 480 Pa absolute pressure within 35 minutes, the reaction temperature is 258 °C, the reaction time is 45 minutes, and then continue to vacuum Carry out the polycondensation reaction in the high vacuum stage to further reduce the reaction pressure to an absolute pressure of 96Pa, the reaction temperature is 270°C, the reaction time is 55min, and a modified polyester with a number average molecular weight of 26000 and a molecular weight distribution index of 1.9 is prepared;
  • Modified polyester FDY yarns are obtained after the polyester melt is metered, spinneret extruded, cooled, oiled, drawn, heat set and wound, that is, degradable polyester fibers are obtained.
  • the parameters of the FDY process are : Spinning temperature 290°C, cooling temperature 20°C, network pressure 0.25MPa, one-roller speed 2500m/min, one-roller temperature 85°C, second-roller speed 4000m/min, second-roller temperature 120°C, winding speed 4000m/min.
  • the monofilament fineness of the degradable polyester fiber is 1.5dtex, the breaking strength is 3.2cN/dtex, the elongation at break is 34%, the network degree is 14/m, the linear density deviation rate is 0.8%, the breaking strength CV value 4.5%, breaking elongation CV value is 8.2%, boiling water shrinkage is 6.3%;
  • a preparation method of degradable polyester fiber the steps are as follows:
  • Terephthalic acid ethylene glycol, 2,5,6,6-tetramethyl-2,5-heptanediol and 2,2,3,3-tetrafluoro-1,4-succinic acid are formulated into a slurry After adding doped and modified ZrO 2 powder, antimony acetate, titanium dioxide and triphenyl phosphate, and mixing them evenly, the esterification reaction is carried out under pressure in a nitrogen atmosphere.
  • the pressure is 0.15 MPa and the temperature of the esterification reaction is 260 °C, when the amount of water distilled in the esterification reaction reaches 95% of the theoretical value, it is the end point of the esterification reaction, the molar ratio of terephthalic acid and ethylene glycol is 1:1.5, 2,5,6,6-four
  • the addition amounts of antimony acetate, titanium dioxide and triphenyl phosphate are 0.24wt%, 0.05wt%, 2.0wt% and 0.01wt% of the
  • the polycondensation reaction in the low vacuum stage is started under negative pressure.
  • the pressure in this stage is steadily pumped from normal pressure to 480 Pa absolute pressure within 50 minutes, the reaction temperature is 255 °C, the reaction time is 50 minutes, and then continue to vacuum Carry out the polycondensation reaction in the high vacuum stage to further reduce the reaction pressure to 95Pa absolute pressure, the reaction temperature is 282°C, the reaction time is 80min, and a modified polyester with a number average molecular weight of 29000 and a molecular weight distribution index of 2.1 is prepared;
  • Modified polyester FDY yarns are obtained after the polyester melt is metered, spinneret extruded, cooled, oiled, drawn, heat set and wound, that is, degradable polyester fibers are obtained.
  • the parameters of the FDY process are : Spinning temperature 295°C, cooling temperature 19°C, network pressure 0.20MPa, one-roll speed 2300m/min, one-roll temperature 80°C, two-roll speed 3800m/min, two-roll temperature 115°C, winding speed 3730m/min.
  • the monofilament fineness of the degradable polyester fiber is 1.5dtex, the breaking strength is 3.2cN/dtex, the elongation at break is 32%, the network degree is 12/m, the linear density deviation rate is 0.9%, and the breaking strength CV value It is 4.6%, the breaking elongation CV value is 8.5%, and the boiling water shrinkage is 6.5%;
  • a preparation method of degradable polyester fiber the steps are as follows:
  • Terephthalic acid ethylene glycol, 2,5,6,6-tetramethyl-2,5-heptanediol and 2,2,3,3-tetrafluoro-1,4-succinic acid are formulated into a slurry After adding doped and modified ZrO 2 powder, antimony acetate, titanium dioxide and triphenyl phosphate, and mixing them evenly, the esterification reaction is carried out under pressure in a nitrogen atmosphere.
  • the pressure is 0.3 MPa and the temperature of the esterification reaction is 250 °C, when the amount of water distilled in the esterification reaction reaches 95% of the theoretical value is the end point of the esterification reaction, the molar ratio of terephthalic acid to ethylene glycol is 1:1.6, 2,5,6,6-four
  • the sum of the addition amounts of methyl-2,5-heptanediol and 2,2,3,3-tetrafluoro-1,4-succinic acid is 5.2mol% of the addition amount of terephthalic acid, 2,5,6 , 6-tetramethyl-2,5-heptanediol and 2,2,3,3-tetrafluoro-1,4-succinic acid molar ratio is 1.2:1, doped with modified ZrO 2 powder,
  • the addition amounts of antimony acetate, titanium dioxide and triphenyl phosphate are 0.25wt%, 0.05wt%, 2.8wt% and 0.01wt% of the addition amount
  • the polycondensation reaction in the low-vacuum stage is started under negative pressure.
  • the pressure in this stage is steadily pumped from normal pressure to an absolute pressure of 450 Pa within 30 minutes, the reaction temperature is 260 °C, the reaction time is 30 minutes, and then continue to vacuum Carry out the polycondensation reaction in the high vacuum stage to further reduce the reaction pressure to an absolute pressure of 92Pa, the reaction temperature is 272°C, the reaction time is 85min, and a modified polyester with a number average molecular weight of 28000 and a molecular weight distribution index of 1.8 is prepared;
  • Modified polyester FDY yarns are obtained after the polyester melt is metered, spinneret extruded, cooled, oiled, drawn, heat set and wound, that is, degradable polyester fibers are obtained.
  • the parameters of the FDY process are : Spinning temperature 295°C, cooling temperature 19°C, network pressure 0.20MPa, one-roll speed 2300m/min, one-roll temperature 80°C, two-roll speed 3800m/min, two-roll temperature 115°C, winding speed 3730m/min.
  • the monofilament fineness of the degradable polyester fiber is 1.5dtex, the breaking strength is 3.2cN/dtex, the elongation at break is 30%, the network degree is 11 pieces/m, the linear density deviation rate is 1.0%, the breaking strength CV value It is 4.8%, the breaking elongation CV value is 8.6%, the boiling water shrinkage is 6.7%;
  • a preparation method of degradable polyester fiber the steps are as follows:
  • Terephthalic acid ethylene glycol, 2,5,6,6-tetramethyl-2,5-heptanediol and 2,2-difluoro-1,3-malonic acid are mixed into a slurry, and doping is added After the modified ZrO 2 powder, antimony trioxide, titanium dioxide and trimethyl phosphite are uniformly mixed, the esterification reaction is carried out under pressure in a nitrogen atmosphere.
  • the pressure is 0.2 MPa and the temperature of the esterification reaction is 255°C
  • the molar ratio of terephthalic acid and ethylene glycol is 1:1.6, 2,5,6,6-tetramethyl
  • the sum of the added amounts of yl-2,5-heptanediol and 2,2-difluoro-1,3-malonic acid is 5.4mol% of the added amount of terephthalic acid, 2,5,6,6-tetramethyl
  • the molar ratio of hydroxy-2,5-heptanediol and 2,2-difluoro-1,3-malonic acid is 2:1.5, and doped modified ZrO 2 powder, antimony trioxide, titanium dioxide and phosphorous acid
  • the addition amount of trimethyl ester is 0.25wt%, 0.04wt%, 3.0wt% and 0.05wt% of the addition amount of terephthalic acid;
  • the polycondensation reaction in the low-vacuum stage is started under negative pressure.
  • the pressure in this stage is steadily pumped from normal pressure to absolute pressure within 490 Pa, the reaction temperature is 255 °C, the reaction time is 50 min, and then continue to vacuum Carry out the polycondensation reaction in the high vacuum stage to further reduce the reaction pressure to 95Pa absolute pressure, the reaction temperature is 275°C, the reaction time is 55min, and a modified polyester with a number average molecular weight of 25,000 and a molecular weight distribution index of 2.2 is prepared;
  • Modified polyester FDY yarns are obtained after the polyester melt is metered, spinneret extruded, cooled, oiled, drawn, heat set and wound, that is, degradable polyester fibers are obtained. : Spinning temperature 285°C, cooling temperature 22°C, network pressure 0.30MPa, one-roll speed 2700m/min, one-roll temperature 90°C, two-roll speed 4200m/min, second-roll temperature 130°C, winding speed 4120m/min.
  • the monofilament fineness of the degradable polyester fiber is 1.0 dtex, the breaking strength is 3.1 cN/dtex, the elongation at break is 30%, the network degree is 15 pieces/m, the linear density deviation rate is 1.0%, and the breaking strength CV value It is 4.7%, the breaking elongation CV value is 8.8%, the boiling water shrinkage is 6.8%;
  • a preparation method of degradable polyester fiber the steps are as follows:
  • Terephthalic acid ethylene glycol, 2,5,6,6-tetramethyl-2,5-heptanediol and 2,2-difluoro-1,3-malonic acid are mixed into a slurry, and doping is added
  • the esterification reaction is carried out under pressure in a nitrogen atmosphere, the pressure is 0.3MPa, and the temperature of the esterification reaction is 255°C.
  • the molar ratio of terephthalic acid to ethylene glycol is 1:2.0, 2,5,6,6-tetramethyl -The sum of the addition of 2,5-heptanediol and 2,2-difluoro-1,3-malonic acid is 5.8mol% of the addition of terephthalic acid, 2,5,6,6-tetramethyl -The molar ratio of -2,5-heptanediol and 2,2-difluoro-1,3-malonic acid is 2:1, doped with modified ZrO 2 powder, ethylene glycol antimony, titanium dioxide and triphenyl phosphate
  • the amount of ester added is 0.25wt%, 0.04wt%, 2.0wt% and 0.03wt% of the amount of terephthalic acid added;
  • the polycondensation reaction in the low-vacuum stage starts under negative pressure.
  • the pressure in this stage is steadily pumped from normal pressure to 480 Pa absolute pressure within 50 minutes, the reaction temperature is 260 °C, the reaction time is 40 minutes, and then continue to vacuum Carry out the polycondensation reaction in the high vacuum stage to further reduce the reaction pressure to 95Pa absolute pressure, the reaction temperature is 272°C, the reaction time is 90min, and a modified polyester with a number average molecular weight of 29000 and a molecular weight distribution index of 2.1 is prepared;
  • Modified polyester FDY yarns are obtained after the polyester melt is metered, spinneret extruded, cooled, oiled, drawn, heat set and wound, that is, degradable polyester fibers are obtained. : Spinning temperature 285°C, cooling temperature 22°C, network pressure 0.30MPa, one-roll speed 2700m/min, one-roll temperature 90°C, two-roll speed 4200m/min, second-roll temperature 130°C, winding speed 4120m/min.
  • the monofilament fineness of the degradable polyester fiber is 1.0 dtex, the breaking strength is 3.0 cN/dtex, the elongation at break is 29%, the network degree is 11 pcs/m, the linear density deviation rate is 1.0%, and the breaking strength CV value Is 5.0%, the breaking elongation CV value is 8.8%, the boiling water shrinkage is 7.0%;

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Engineering & Computer Science (AREA)
  • Medicinal Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • Textile Engineering (AREA)
  • General Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Polyesters Or Polycarbonates (AREA)
  • Artificial Filaments (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
  • Biological Depolymerization Polymers (AREA)

Abstract

一种可降解的聚酯纤维及其制备方法，制备方法为：按FDY工艺由改性聚酯熔体制得改性聚酯FDY丝，即得可降解的聚酯纤维；改性聚酯的分子链包括对苯二甲酸链段、乙二醇链段、2,5,6,6-四甲基-2,5-庚二醇链段和含氟二元酸链段；含氟二元酸为2,2-二氟-1,3-丙二酸、2,2-二氟-1,4-丁二酸、2,2-二氟-1,5-戊二酸或2,2,3,3-四氟-1,4-丁二酸；改性聚酯中分散有掺杂改性的ZrO 2粉体。制得产品在温度为25℃且相对湿度为65％的条件下放置60个月后，其特性粘度下降23～28％。所述制备方法，成本低廉，工艺简单；制得产品，自然降解速率快，极具应用前景。

Description

可降解的聚酯纤维及其制备方法 技术领域
本发明属于聚酯纤维技术领域，涉及一种可降解的聚酯纤维及其制备方法。
背景技术
化学纤维的问世，始于20世纪20年代有机合成化学和高分子化学的发展，之后短短数十年它已经成为产业中的支柱，其产量与应用远远超过了天然纤维。其中涤纶、尼龙、腈纶是化纤中的三大纤维，而这三大纤维中又因涤纶的发展速度最快，应用最广泛，产量最高，成为化学纤维之冠，是当今最重要的纺织材料之一。
聚酯纤维是合成纤维的第一大品种，它是以精对苯二甲酸(PTA)或对苯二甲酸二甲酯(DMT)和乙二醇(EG)为原料经酯化或酯交换和缩聚反应而制得的成纤高聚物一聚对苯二甲酸乙二醇酯(PET)，经纺丝和后处理制成的纤维。作为半结晶高分子聚合物具有良好的热塑性，普遍应用于服用、包装、生物、生产加工等各个领域。随着PET产业的快速发展，虽然PET不会直接对环境造成危害，但由于其使用后的废品数目巨大且对大气和微生物试剂的抵抗性很强，PET废弃物已成为全球性的环境污染有机物。超细旦纤维绝大多数运用于服装领域，随着人们对服装需求的不断提升，废旧服装的数量也逐年攀升，在我国每年就产生近3000万吨的废旧服装。目前，常见的对PET废弃物的处理方法有填埋、焚烧及回收利用，填埋和焚烧虽然是最简单的方法，对环境亦将造成一定的污染，降解回收是处理PET废弃物有效而科学的途径，但由于PET结构致密，结晶度高，自然降解时间很长，目前回收利用的比例还很小，最高约13％，虽然近年来我国在PET回收利用方面有较大的增速，但其回收率仍然很低，不到10％。
在实际应用中对于PET的降解多采用化学降解的方法，化学分解法主要有水解法和醇解法，此外还有氨解、胺解和热解等。但目前所使用的化学降解法依然存在降解速率慢，降解效果差等问题，其仍然无法解决大量的废旧服装的降解回收利用。基于环境意识的增强、资源节约及可持续性的需求，服用聚酯纤维(涤纶长丝)的自然降解已成为我国科技工作者迫切需要解决的问题。
因此，研究一种通过对聚酯进行改性来提高聚酯降解速率和降解效果的方法并采用该改性聚酯来制备性能优异的涤纶纤维极具现实意义。
发明内容
本发明的目的是现有技术降解速率慢的缺陷，提供一种自然降解速率快的聚酯纤维及其制备方法。
为了达到上述目的，本发明采用了如下的技术方案：
可降解的聚酯纤维的制备方法，按FDY工艺由改性聚酯熔体制得改性聚酯FDY丝，即得可降解的聚酯纤维；
所述改性聚酯的制备方法为：将对苯二甲酸、乙二醇、2,5,6,6-四甲基-2,5-庚二醇、含氟二元酸和掺杂改性的ZrO 2粉体混合均匀后先后进行酯化反应和缩聚反应；
2,5,6,6-四甲基-2,5-庚二醇的结构式如下：
Figure PCTCN2019113873-appb-000001
含氟二元酸为2,2-二氟-1,3-丙二酸、2,2-二氟-1,4-丁二酸、2,2-二氟-1,5-戊二酸或2,2,3,3-四氟-1,4-丁二酸；
ZrO 2掺杂改性的过程为：首先将含金属离子M x+的溶液与含Zr 4+的溶液混合均匀，然后滴加沉淀剂至混合液的pH值为9～10，最后煅烧沉淀产物；金属离子M x+为Mg 2+、Li +和Zn 2+中的一种以上。
本发明使用2,5,6,6-四甲基-2,5-庚二醇对聚酯进行改性，2,5,6,6-四甲基-2,5-庚二醇能够显著增大改性聚酯的空间自由体积，特别是2,5,6,6-四甲基-2,5-庚二醇中叔丁基的存在会引起主链活动性的变化，从而改变了链单元间的相互作用力，分子链单元间的距离亦会发生相应的改变，增大改性聚酯空洞自由体积。空洞自由体积相比于狭缝自由体积更利于空气、水等分子扩散到纤维内部，能够降低空气、水等分子渗透进入改性聚酯内部的难度，一定程度上提高改性聚酯的自然降解性能。
本发明还通过添加含氟二元酸和掺杂改性的ZrO 2粉体进一步提高改性聚酯的自然降解性能；
本发明的含氟二元酸的特殊之处在于氟原子在α碳上，当在水解过程中引入该含氟二元酸时，由于氟原子在α碳上，吸电子能力较强，使得聚酯中C-O键上的电子云密度降低，四面体的负离子的稳定性下降，有利于亲核加成反应的进行，同时由于α碳上含氟二元酸的空间位阻小于对苯二甲酸，进一步促进了亲核加成反应的进行，因而显著提高了降解速率。
本发明通过先溶液共混再共沉淀再煅烧的方法实现了金属氧化物(氧化镁、氧化锂和氧化锌中的一种以上)与ZrO 2的掺杂，进而对ZrO 2的氧还原催化过程产生影响，提升了聚酯的降解速率。由于本发明选用了离子电导率高的ZrO 2作为氧还原催化剂基材，其通过掺杂低价态的金属离子(Mg 2+、Li +及Zn 2+)能够获得稳定的立方相，同时在一定程度上，掺杂离子半径越接近被掺杂的离子半径，越有利于氧空位的形成，越有利于氧离子的传导，本发明选择掺杂与Zr 4+离子半径相同的金属离子(Mg 2+、Li +及Zn 2+，离子半径均为0.103nm)对其进行掺杂，这能够提高氧离子的传导速率，进而提高氧还原反应的程度。
本发明引入的2,5,6,6-四甲基-2,5-庚二醇、含氟二元酸和掺杂改性的ZrO 2粉体还能起到协同作用，含氟二元酸降低了C-O键上的电子云密度，促进亲核加成反应的进行，有利于降解反应，掺杂改性的ZrO 2粉体提高了氧离子的传导速率，进而提高氧还原反应的程度，进一步促进了自然降解反应，2,5,6,6-四甲基-2,5-庚二醇增大了聚酯的空洞自由体积，有利于氧和水的渗透，提高了聚酯内部氧原子的浓度，三者共同作用显著地提高了降解速率。
作为优选的技术方案：
如上所述的可降解的聚酯纤维纤维的制备方法，所述2,5,6,6-四甲基-2,5-庚二醇的合成步骤如下：
(1)按1～1.2:1:1.2～1.3:2.0～3.0的摩尔比将KOH粉末、3-甲基-3-羟基丁炔、3,3-二甲基-2-丁酮和异丙醚混合，在冰浴条件下反应2～4h，反应结束后进行冷却结晶、离心分离、洗涤、精制和干燥得到辛炔二醇；
(2)按2～3:10:0.01～0.03的重量比将辛炔二醇、乙醇和钯催化剂混合，在40～50℃的温度条件下反应50～60min，反应过程中持续通入氢气，反应结束后进行分离和提纯得到2,5,6,6-四甲基-2,5-庚二醇。
如上所述的可降解的聚酯纤维纤维的制备方法，所述含金属离子M x+的溶液的浓度为1～2wt％，溶剂为水，溶液中的阴离子为NO 3 -；所述含Zr 4+的溶液为浓度20～25wt％的ZrO 2的溶液，溶剂为硝酸；所述沉淀剂为浓度2mol/L的氨水；沉淀开始时，混合液中金属离子M x+与Zr 4+的摩尔比为5～8:100，本发明金属离子M x+与Zr 4+的摩尔比并不限于此，本领域技术人员可根据实际情况进行调整，但调整幅度不宜过大，这是因为催化剂中ZrO 2是主体，金属离子M x+的引入是围绕ZrO 2展开的，目的是提高氧离子的传导速率，进而提高氧还原反应的程度，若摩尔比过大会主次不分，过少则对提高氧离子的传导速率作用不足；
所述煅烧前对沉淀产物进行洗涤和干燥，干燥的温度为105～110℃，时间为2～3h；所述煅烧的过程为：首先升温至400℃后保温2～3h，然后升温至700℃后保温1～2h，最后在空气中冷却；ZrO 2在掺杂改性后进行粉碎得到平均粒径小于0.5微米的粉体。
如上所述的可降解的聚酯纤维纤维的制备方法，所述改性聚酯的制备步骤如下：
(1)酯化反应；
将对苯二甲酸、乙二醇、2,5,6,6-四甲基-2,5-庚二醇和含氟二元酸配成浆料，加入掺杂改性的ZrO 2粉体、催化剂、消光剂和稳定剂混合均匀后，在氮气氛围中加压进行酯化反应，加压压力为常压～0.3MPa，酯化反应的温度为250～260℃，当酯化反应中的水馏出量达到理论值的90％以上时为酯化反应终点；
(2)缩聚反应；
酯化反应结束后，在负压条件下开始低真空阶段的缩聚反应，该阶段压力在30～50min内由常压平稳抽至绝对压力500Pa以下，反应温度为250～260℃，反应时间为30～50min，然后继续抽真空，进行高真空阶段的缩聚反应，使反应压力进一步降至绝对压力100Pa以下，反应温度为270～282℃，反应时间为50～90min。
如上所述的可降解的聚酯纤维纤维的制备方法，所述对苯二甲酸与乙二醇的摩尔比为1:1.2～2.0，所述2,5,6,6-四甲基-2,5-庚二醇和含氟二元酸的加入量之和为对苯二甲酸加入量的4～6mol％，所述2,5,6,6-四甲基-2,5-庚二醇与含氟二元酸的摩尔比为1～2:1～2，所述掺杂改性的ZrO 2粉体、催化剂、消光剂和稳定剂的加入量分别为对苯二甲酸加入量的0.23～0.25wt％、0.03～0.05wt％、0.20～0.25wt％和0.01～0.05wt％。2,5,6,6-四甲基-2,5-庚二醇的添加量过多(如大于0.1)，对聚酯大分子结构的规整性破坏太大，对纤维的结晶度以及力学性能(刚性)影响过大，不利于纤维的生产和应用；添加量过少(如小于0.01)，对聚酯空洞自由体积的增大不明显，难以显著提升聚酯的自然降解性能。 本发明的掺杂改性的ZrO 2粉体的加入量并不限于此，本领域技术人员可实际情况进行调整，但调整幅度不宜过大，添加量过大对纤维的光泽以及力学性能等影响较大，不利于纤维的生产和应用，添加量过低，则效果(对自然降解性能的提升)不明显。本发明的含氟二元酸的加入量并不限于此，本领域技术人员可实际情况进行调整，但调整幅度不宜过大，添加量过大对聚酯大分子结构的规整性破坏太大，对纤维的结晶度以及力学性能影响过大，不利于纤维的生产和应用，添加量过低，则效果(对自然降解性能的提升)不明显。
如上所述的可降解的聚酯纤维纤维的制备方法，所述催化剂为三氧化二锑、乙二醇锑或醋酸锑，所述消光剂为二氧化钛，所述稳定剂为磷酸三苯酯、磷酸三甲酯或亚磷酸三甲酯。
如上所述的可降解的聚酯纤维纤维的制备方法，改性聚酯的数均分子量为25000～30000，分子量分布指数为1.8～2.2。
如上所述的可降解的聚酯纤维纤维的制备方法，所述FDY工艺的流程为：计量、喷丝板挤出、冷却、上油、拉伸、热定型和卷绕；
所述FDY工艺的参数为：纺丝温度285～295℃，冷却温度19～22℃，网络压力0.20～0.30MPa，一辊速度2300～2700m/min，一辊温度80～90℃，二辊速度3800～4200m/min，二辊温度115～130℃，卷绕速度3730～4120m/min。本发明的FDY工艺的具体参数并不仅限于此，此处仅给出一可行的工艺参数。
本发明还提供采用如上所述的可降解的聚酯纤维的制备方法制得的可降解的聚酯纤维，为改性聚酯FDY丝；
所述改性聚酯的分子链包括对苯二甲酸链段、乙二醇链段、2,5,6,6-四甲基-2,5-庚二醇链段和含氟二元酸链段；
所述改性聚酯中分散有掺杂改性的ZrO 2粉体；掺杂改性的过程为：首先将含金属离子M x+的溶液与含Zr 4+的溶液混合均匀，然后滴加沉淀剂至混合液的pH值为9～10，最后煅烧沉淀产物；金属离子M x+为Mg 2+、Li +和Zn 2+中的一种以上。
作为优选的技术方案：
如上所述的可降解的聚酯纤维，可降解的聚酯纤维的单丝纤度为1.0～2.0dtex，断裂强度≥3.0cN/dtex，断裂伸长率为32.0±4.0％，网络度为13±2个/m，线密度偏差率≤1.0％，断裂强度CV值≤5.0％，断裂伸长CV值≤9.0％，沸水收缩率为6.5±0.5％，本发明的2,5,6,6-四甲基-2,5-庚二醇、含氟二元酸和掺杂改性的ZrO 2粉体的添加量较小，其对聚酯纤维的加工及机械性能的影响较小，本发明的可降解的聚酯纤维的加工性能及机械性能与普通聚酯纤维(未添加2,5,6,6-四甲基-2,5-庚二醇、含氟二元酸和掺杂改性的ZrO 2粉体)相当；
可降解的聚酯纤维在温度为25℃且相对湿度为65％的条件下放置60个月后，其特性粘度下降23～28％；相同条件下，对比样的特性粘度下降4.3％，对比样与本发明的改性聚酯FDY丝的区别仅在于其材质为普通聚酯且未添加掺杂改性的ZrO 2粉体，本发明的可降解的聚酯纤维相比于常规PET纤维自然降解速率显著增加，2,5,6,6-四甲基-2,5-庚二醇、含氟二元酸和掺杂改性的ZrO 2粉体能够显著提升纤维的自然降解速率。
发明机理：
聚合物中的大分子链不是完全紧密的堆砌，在大分子链之间总是有空隙存在，这部分空隙体积即为自由体积。要使小分子渗透到高分子内部，高分子内或高分子间要有足够大的空隙，所以小分子的渗透率和扩散性与高分子结构中的空隙大小(即自由体积的尺寸)有关，在一定范围内，自由体积的尺寸越大，小分子的渗透率越高，扩散性越好。自由体积又分为空洞自由体积和狭缝自由体积，空洞自由体较狭缝自由体积具更大的空间尺寸，对于小分子的渗透率的提升，空洞自由体积较狭缝自由体积效果更加明显。
自由体积的尺寸和类型主要取决于聚合物的结构，影响聚合物结构的主要因素为立体阻碍、侧基大小、侧基结构等。当聚合物主链上某一位置被侧基取代时，必然引起主链活动性的变化，从而改变了链与链间的相互作用力，链与链间的距离亦会发生相应的改变，结果导致内聚能和自由体积的变化，高分子侧链上的取代基的极性、大小、长短等对分子链的刚性、分子间的相互作用乃至聚合物结构的自由体积分数都有一定的影响，因此，取代基不同产生的效应不同，往往导致聚合物的渗透分离性能也各不相同。
对于乙二醇、丁二醇等二元醇直链分子，主链上的C原子处于一上一下呈锯齿形排列，当主链上某个亚甲基上的两个H原子被甲基(-CH 3)取代时，这两个侧基上的C原子与主链C原子不在同一平面内，于是，中心C上的四个sp3杂化轨道分别与周围四个C原子上的空轨道重叠，形成四个完全相同的σ键，呈正四面体排列，四个碳原子分别位于正四面体的四个顶点，当甲基的三个氢进一步被甲基取代时，这时就相当于叔丁基取代，形成一个更大的 四面体结构，这种呈正四面体形排列的分子链相对于呈锯齿形排列的分子链，空洞自由体积明显增大了很多，能够显著提高小分子的渗透率和扩散性；而当主链上某个亚甲基上的两个H原子被长支链取代基取代时，主要增大的是狭缝自由体积，增大幅度较小，对小分子的渗透率和扩散性的提升效果有限，同时由于长支链取代基的刚性较小，分子链之间容易发生缠结，不利于自由体积的增大。
本发明通过在聚酯分子链中引入2,5,6,6-四甲基-2,5-庚二醇显著提升了聚酯纤维的自然降解性能，2,5,6,6-四甲基-2,5-庚二醇的结构式如下：
Figure PCTCN2019113873-appb-000002
2,5,6,6-四甲基-2,5-庚二醇中叔丁基的存在会引起主链活动性的变化，从而改变了链单元间的相互作用力，分子链单元间的距离亦会发生相应的改变，导致改性聚酯的空洞自由体积增大。与短支链取代基(如甲基、乙基等基团)相比，叔丁基占据了较大的空间位置，在分子链排列的方式上将获得更大的自由体积；与长支链取代基相比，一方面叔丁基增大的是空洞自由体积，而长支链取代基增大的是狭缝自由体积，另一方面叔丁基的刚性大于长支链取代基，减少了分子链之间的缠结，因而叔丁基较长支链取代基在分子链排列的方式上具有更多的自由体积。由于对于空气、水等分子向纤维内部的扩散而言，空洞自由体积比狭缝自由体积的提高更佳，本发明通过增大空洞自由体积，使得水或其它分子如空气等更容易渗透到改性聚酯大分子内部，对改性聚酯的自然降解性能等产生积极的影响。
聚酯在碱性条件下的水解降解过程为亲核加成-消除过程，在水解反应开始时，OH -进攻酯羰基RCOOR`的C原子，发生亲核加成反应，形成中间体(即四面体的负离子)，四面体的负离子可以消除OR`得到羧酸RCOOH，使酯键断裂，同时OR`与H +结合得到醇HOR`。然而，由于在水解过程中形成的四面体的负离子结构比较拥挤，空间位阻大，不利于亲核加成反应的进行，因此聚酯的降解速率较慢。
本发明通过在聚酯分子链中引入特殊结构的含氟二元酸显著提高了聚酯的降解速率，含氟二元酸的特殊之处在于氟原子在α碳上，当在水解过程中引入该含氟二元酸时，由于氟原子在α碳上，吸电子能力较强，使得聚酯中C-O键上的的电子云密度降低，四面体的负离子的稳定性下降，有利于亲核加成反应的进行，同时由于α碳上含氟二元酸的空间位阻小于对苯二甲酸，进一步促进了亲核加成反应的进行，因而显著提高了降解速率。如在聚酯分子链中引入氟原子在β碳的含氟二元酸，则不会显著提高聚酯的降解速率，这是因为在β碳上存在吸电子基团时，所产生的影响仅局限于相邻碳上，而对酯键中C-O键产生的影响很小，因而对于OH -进攻酯羰基发生亲核加成的反应影响较小。
当聚酯中含有一定量的氧还原催化剂时，由于聚酯长期暴露在空气中，空气中的氧气能够通过聚酯材质中的自由体积(窄缝自由体积和/或空洞自由体积)渗入聚酯内部，氧还原催化剂表面吸附氧气，氧气逐渐迁移到聚酯内部的氧还原催化剂表面，达到一定氧浓度梯度后形成吸附氧，在氧还原催化剂表面发生氧还原反应(氧离子化)，在这一反应过程中，氧气被部分还原为过氧化物，氧还原催化剂吸附后的氧气分子与一个聚酯中的酯键结合并在催化剂表面形成RCOOOR`，后再结合一个质子并断开氧氧键，生成一个RCOOH，使酯键断裂，同时OR`与H +结合得到醇HOR`，从而加速了聚酯降解。
本发明通过先溶液共混再共沉淀再煅烧的方法实现了金属氧化物(氧化镁、氧化锂和氧化锌中的一种以上)与ZrO 2的掺杂，进而对ZrO 2的氧还原催化过程产生影响，提升了聚酯的降解速率。由于本发明选用了离子电导率高的ZrO 2作为氧还原催化剂基材，其通过掺杂低价态的金属离子(Mg 2+、Li +及Zn 2+)能够获得稳定的立方相，同时在一定程度上，掺杂离子半径越接近被掺杂的离子半径，越有利于氧空位的形成，越有利于氧离子的传导，本发明选择掺杂与Zr 4+离子半径相同的金属离子(Mg 2+、Li +及Zn 2+，离子半径均为0.103nm)对其进行掺杂，这能够提高氧离子的传导速率，进而提高氧还原反应的程度。掺杂对ZrO 2的影响如下：
一方面，采用本发明的掺杂方式能够破坏ZrO 2的晶面结构，增大了其比表面积，进而提高了单位质量ZrO 2的氧气吸附量；
另一方面，采用本发明的掺杂方式能够改变ZrO 2的吸附方式和氧还原反应机制，掺杂改性前，吸附方式为单斜ZrO 2表面的端式吸附，O原子在不同单斜ZrO 2晶面吸附时，都会受到表面Zr原子的“空间位阻效应”影响，O 2 分子通过强度较弱的物理吸附或弱化学吸附在Zr原子位吸附，且在不同单斜ZrO 2晶面O 2分子都还原为过氧化物，掺杂改性后，吸附方式为掺杂ZrO 2表面的侧式吸附，其不受“空间位阻效应”影响，增强了O 2分子在Zr原子位的化学吸附，还能促进O 2分子的O-O键断裂，即可以促进O 2分子还原生成过氧化物，提高了氧还原催化效率进而提高了聚酯降解速率。如仅将金属氧化物(氧化镁、氧化锂和氧化锌中的一种以上)与ZrO 2物理共混，金属氧化物不会影响ZrO 2的晶面结构，也会改变其吸附方式和氧还原反应机制，因而不会提高氧还原催化效率，也会不提高聚酯降解速率。
由于聚酯内部氧还原催化剂的存在，氧气能够在聚酯内部长时间的停留，能够对聚酯中最薄弱的酯基进行氧化反应，加速了聚酯降解的程度。现有技术的降解聚酯均是从聚酯表面开始的，而本发明通过将氧还原催化剂混入聚酯，提供了一种从聚酯内部降解的新思路。
本发明引入的2,5,6,6-四甲基-2,5-庚二醇、含氟二元酸和掺杂改性的ZrO 2粉体还能起到协同作用，含氟二元酸降低了C-O键上的电子云密度，促进亲核加成反应的进行，有利于降解反应，掺杂改性的ZrO 2粉体提高了氧离子的传导速率，进而提高氧还原反应的程度，进一步促进了自然降解反应，2,5,6,6-四甲基-2,5-庚二醇增大了聚酯的空洞自由体积，有利于氧和水的渗透，提高了聚酯内部氧原子的浓度，三者共同作用显著地提高了降解速率。
有益效果：
(1)本发明的可降解的聚酯纤维的制备方法，通过在聚酯中引入改性组分——带2,5,6,6-四甲基-2,5-庚二醇增大空洞自由体积，一定程度上提高了自然降解速率；
(2)本发明的可降解的聚酯纤维的制备方法，通过在聚酯中引入组分——含氟二元酸和掺杂改性的ZrO 2粉体，显著提高了聚酯纤维的自然降解速率；
(3)本发明的可降解的聚酯纤维的制备方法，成本低廉，工艺简单，极具应用前景；
(4)本发明的可降解的聚酯纤维，自然降解速率快，机械性能好，应用前景广阔。
具体实施方式
下面结合具体实施方式，进一步阐述本发明。应理解，这些实施例仅用于说明本发明而不用于限制本发明的范围。此外应理解，在阅读了本发明讲授的内容之后，本领域技术人员可以对本发明作各种改动或修改，这些等价形式同样落于本申请所附权利要求书所限定的范围。
Figure PCTCN2019113873-appb-000003
实施例1
一种可降解的聚酯纤维的制备方法，步骤如下：
(1)制备改性聚酯；
(1.1)制备2,5,6,6-四甲基-2,5-庚二醇；
(a)按1:1:1.2:2.0的摩尔比将KOH粉末、3-甲基-3-羟基丁炔、3,3-二甲基-2-丁酮和异丙醚混合，在冰浴条件下反应2h，反应结束后进行冷却结晶、离心分离、洗涤、精制和干燥得到辛炔二醇；
(b)按2:10:0.01的重量比将辛炔二醇、乙醇和钯催化剂混合，在40℃的温度条件下反应50min，反应过程中持续通入氢气，反应结束后进行分离和提纯得到2,5,6,6-四甲基-2,5-庚二醇，2,5,6,6-四甲基-2,5-庚二醇的结构式如式(Ⅰ)所示；
(1.2)制备掺杂改性的ZrO 2粉体；
(a)将浓度为1.5wt％的Mg(NO 3) 2水溶液与浓度为22wt％的ZrO 2的溶液混合均匀，ZrO 2的溶液的溶剂为硝酸，混合液中Mg 2+与Zr 4+的摩尔比为6:100；
(b)滴加浓度2mol/L的氨水至混合液的pH值为9得到沉淀产物，对沉淀产物进行洗涤和干燥，干燥的温度为108℃，时间为2.5h；
(c)将干燥产物升温至400℃后保温2.5h，然后升温至700℃后保温1.5h，最后在空气中冷却后粉碎得到粒径为0.4微米的掺杂改性的ZrO 2粉体；
(1.3)酯化反应；
对苯二甲酸、乙二醇、2,5,6,6-四甲基-2,5-庚二醇和2,2-二氟-1,3-丙二酸配成浆料，加入掺杂改性的ZrO 2粉体、三氧化二锑、二氧化钛和磷酸三苯酯混合均匀后，在氮气氛围中加压进行酯化反应，加压压力为0.3MPa，酯化反应的温度为250℃，当酯化反应中的水馏出量达到理论值的90％时为酯化反应终点，对苯二甲酸与乙二醇的摩尔比为1:1.5，2,5,6,6-四甲基-2,5-庚二醇和2,2-二氟-1,3-丙二酸的加入量之和为对苯二甲酸加入量的6mol％，2,5,6,6-四甲基-2,5-庚二醇和2,2-二氟-1,3-丙二酸的摩尔比为1:1，掺杂改性的ZrO 2粉体、三氧化二锑、二氧化钛和磷酸三苯酯的加入量分别为对苯二甲酸加入量的0.25wt％、0.05wt％、2.0wt％和0.01wt％；
(1.4)缩聚反应；
酯化反应结束后，在负压条件下开始低真空阶段的缩聚反应，该阶段压力在30min内由常压平稳抽至绝对压力499Pa，反应温度为250℃，反应时间为30min，然后继续抽真空，进行高真空阶段的缩聚反应，使反应压力进一步降至绝对压力99Pa，反应温度为270℃，反应时间为50min，制得数均分子量为25000，分子量分布指数为1.8的改性聚酯；
(2)制备聚酯FDY丝；
聚酯熔体经计量、喷丝板挤出、冷却、上油、拉伸、热定型和卷绕后制得改性聚酯FDY丝，即得可降解的聚酯纤维，FDY工艺的参数为：纺丝温度290℃，冷却温度20℃，网络压力0.25MPa，一辊速度2500m/min，一辊温度85℃，二辊速度4000m/min，二辊温度120℃，卷绕速度4000m/min。
可降解的聚酯纤维的单丝纤度为1.5dtex，断裂强度为3.0cN/dtex，断裂伸长率为28％，网络度为11个/m，线密度偏差率为1.0％，断裂强度CV值为4.8％，断裂伸长CV值为8.7％，沸水收缩率为7.0％；
可降解的聚酯纤维在温度为25℃且相对湿度为65％的条件下放置60个月后，其特性粘度下降28％。
对比例1
一种聚酯纤维的制备方法，与实施例1基本一致，不同之处在于，步骤(1.3)中不添加2,5,6,6-四甲基-2,5-庚二醇、2,2-二氟-1,3-丙二酸和掺杂改性的ZrO 2粉体。最终制得的聚酯纤维的单丝纤度为1.5dtex，断裂强度为3.1cN/dtex，断裂伸长率为27％，网络度为11个/m，线密度偏差率为1.0％，断裂强度CV值为5.0％，断裂伸长CV值为8.7％，沸水收缩率为7.0％；
聚酯纤维在温度为25℃且相对湿度为65％的条件下放置60个月后，其特性粘度下降4％。将实施例1与对比例1相对比可知，本发明通过对聚酯进行改性，大大提高了聚酯纤维的可降解性能且力学性能不受影响。
对比例2
一种聚酯纤维的制备方法，与实施例1基本一致，不同之处在于，步骤(1.3)中采用3,3-二氟戊二酸替代2,2-二氟-1,3-丙二酸，最终制得的聚酯纤维在温度为25℃且相对湿度为65％的条件下放置60个月后，其特性粘度下降14.8％，将实施例1与对比例1相对比可知，由于氟原子在β碳的含氟二元酸的β碳上存在吸电子基团时，所产生的影响仅局限于相邻碳上，而对酯键中C-O键产生的影响很小，因而对于OH -进攻酯羰基发生亲核加成的反应影响较小，进而对纤维的自然降解过程影响较小，因此本发明的氟原子在α碳的含氟二元酸更有利于和掺杂改性的ZrO 2粉体进行协同作用，提升纤维的自然降解性能。
实施例2
一种可降解的聚酯纤维的制备方法，步骤如下：
(1)制备改性聚酯；
(1.1)制备2,5,6,6-四甲基-2,5-庚二醇；
(a)按1.1:1:1.2:2.3的摩尔比将KOH粉末、3-甲基-3-羟基丁炔、3,3-二甲基-2-丁酮和异丙醚混合，在冰浴条件下反应2h，反应结束后进行冷却结晶、离心分离、洗涤、精制和干燥得到辛炔二醇；
(b)按2:10:0.01的重量比将辛炔二醇、乙醇和钯催化剂混合，在45℃的温度条件下反应50min，反应过程中持续通入氢气，反应结束后进行分离和提纯得到2,5,6,6-四甲基-2,5-庚二醇，2,5,6,6-四甲基-2,5-庚二醇的结构式如式(Ⅰ)所示；
(1.2)制备掺杂改性的ZrO 2粉体；
(a)将浓度为1wt％的LiNO 3水溶液与浓度为20wt％的ZrO 2的溶液混合均匀，ZrO 2的溶液的溶剂为硝酸，混合液中Li +与Zr 4+的摩尔比为5:100；
(b)滴加浓度2mol/L的氨水至混合液的pH值为10得到沉淀产物，对沉淀产物进行洗涤和干燥，干燥的温度为105℃，时间为3h；
(c)将干燥产物升温至400℃后保温2h，然后升温至700℃后保温1h，最后在空气中冷却后粉碎得到粒径为0.4微米的掺杂改性的ZrO 2粉体；
(1.3)酯化反应；
对苯二甲酸、乙二醇、2,5,6,6-四甲基-2,5-庚二醇和2,2-二氟-1,4-丁二酸配成浆料，加入掺杂改性的ZrO 2粉体、乙二醇锑、二氧化钛和磷酸三甲酯混合均匀后，在氮气氛围中加压进行酯化反应，加压压力为常压，酯化反应的温度为260℃，当酯化反应中的水馏出量达到理论值的95％时为酯化反应终点，对苯二甲酸与乙二醇的摩尔比为1:1.2，2,5,6,6-四甲基-2,5-庚二醇和2,2-二氟-1,4-丁二酸的加入量之和为对苯二甲酸加入量的4mol％，2,5,6,6-四甲基-2,5-庚二醇和2,2-二氟-1,4-丁二酸的摩尔比为2:2，掺杂改性的ZrO 2粉体、乙二醇锑、二氧化钛和磷酸三甲酯的加入量分别为对苯二甲酸加入量的0.23wt％、0.05wt％、2.2wt％和0.05wt％；
(1.4)缩聚反应；
酯化反应结束后，在负压条件下开始低真空阶段的缩聚反应，该阶段压力在50min内由常压平稳抽至绝对压力450Pa，反应温度为260℃，反应时间为50min，然后继续抽真空，进行高真空阶段的缩聚反应，使反应压力进一步降至绝对压力90Pa，反应温度为282℃，反应时间为90min，制得数均分子量为30000，分子量分布指数为2.2的改性聚酯；
(2)制备聚酯FDY丝；
聚酯熔体经计量、喷丝板挤出、冷却、上油、拉伸、热定型和卷绕后制得改性聚酯FDY丝，即得可降解的聚酯纤维，FDY工艺的参数为：纺丝温度290℃，冷却温度20℃，网络压力0.25MPa，一辊速度2500m/min，一辊温度85℃，二辊速度4000m/min，二辊温度120℃，卷绕速度4000m/min。
可降解的聚酯纤维的单丝纤度为2.0dtex，断裂强度为3.3cN/dtex，断裂伸长率为36％，网络度为15个/m，线密度偏差率为0.8％，断裂强度CV值为4.2％，断裂伸长CV值为8.1％，沸水收缩率为6.0％；
可降解的聚酯纤维在温度为25℃且相对湿度为65％的条件下放置60个月后，其特性粘度下降23％。
实施例3
一种可降解的聚酯纤维的制备方法，步骤如下：
(1)制备改性聚酯；
(1.1)制备2,5,6,6-四甲基-2,5-庚二醇；
(a)按1.2:1:1.25:2.0的摩尔比将KOH粉末、3-甲基-3-羟基丁炔、3,3-二甲基-2-丁酮和异丙醚混合，在冰浴条件下反应3h，反应结束后进行冷却结晶、离心分离、洗涤、精制和干燥得到辛炔二醇；
(b)按3:10:0.03的重量比将辛炔二醇、乙醇和钯催化剂混合，在40℃的温度条件下反应50min，反应过程中持续通入氢气，反应结束后进行分离和提纯得到2,5,6,6-四甲基-2,5-庚二醇，2,5,6,6-四甲基-2,5-庚二醇的结构式如式(Ⅰ)所示；
(1.2)制备掺杂改性的ZrO 2粉体；
(a)将浓度为2wt％的Zn(NO 3) 2水溶液与浓度为25wt％的ZrO 2的溶液混合均匀，ZrO 2的溶液的溶剂为硝酸，混合液中Zn 2+与Zr 4+的摩尔比为8:100；
(b)滴加浓度2mol/L的氨水至混合液的pH值为10得到沉淀产物，对沉淀产物进行洗涤和干燥，干燥的温度为110℃，时间为2h；
(c)将干燥产物升温至400℃后保温3h，然后升温至700℃后保温2h，最后在空气中冷却后粉碎得到粒径为0.4微米的掺杂改性的ZrO 2粉体；
(1.3)酯化反应；
对苯二甲酸、乙二醇、2,5,6,6-四甲基-2,5-庚二醇和2,2-二氟-1,5-戊二酸配成浆料，加入掺杂改性的ZrO 2粉体、醋酸锑、二氧化钛和亚磷酸三甲酯混合均匀后，在氮气氛围中加压进行酯化反应，加压压力为0.2MPa，酯化反应的温度为255℃，当酯化反应中的水馏出量达到理论值的95％时为酯化反应终点，对苯二甲酸与乙二醇的摩尔比为 1:1.5，2,5,6,6-四甲基-2,5-庚二醇和2,2-二氟-1,5-戊二酸的加入量之和为对苯二甲酸加入量的4.4mol％，2,5,6,6-四甲基-2,5-庚二醇和2,2-二氟-1,5-戊二酸的摩尔比为1:2，掺杂改性的ZrO 2粉体、醋酸锑、二氧化钛和亚磷酸三甲酯的加入量分别为对苯二甲酸加入量的0.23wt％、0.05wt％、2.3wt％和0.01wt％；
(1.4)缩聚反应；
酯化反应结束后，在负压条件下开始低真空阶段的缩聚反应，该阶段压力在40min内由常压平稳抽至绝对压力480Pa，反应温度为255℃，反应时间为40min，然后继续抽真空，进行高真空阶段的缩聚反应，使反应压力进一步降至绝对压力95Pa，反应温度为272℃，反应时间为70min，制得数均分子量为27000，分子量分布指数为2.0的改性聚酯；
(2)制备聚酯FDY丝；
聚酯熔体经计量、喷丝板挤出、冷却、上油、拉伸、热定型和卷绕后制得改性聚酯FDY丝，即得可降解的聚酯纤维，FDY工艺的参数为：纺丝温度290℃，冷却温度20℃，网络压力0.25MPa，一辊速度2500m/min，一辊温度85℃，二辊速度4000m/min，二辊温度120℃，卷绕速度4000m/min。
可降解的聚酯纤维的单丝纤度为1.0dtex，断裂强度为3.3cN/dtex，断裂伸长率为35％，网络度为14个/m，线密度偏差率为0.9％，断裂强度CV值为4.3％，断裂伸长CV值为8.1％，沸水收缩率为6.2％；
可降解的聚酯纤维在温度为25℃且相对湿度为65％的条件下放置60个月后，其特性粘度下降24％。
实施例4
一种可降解的聚酯纤维的制备方法，步骤如下：
(1)制备改性聚酯；
(1.1)制备2,5,6,6-四甲基-2,5-庚二醇；
(a)按1.2:1:1.3:2.5的摩尔比将KOH粉末、3-甲基-3-羟基丁炔、3,3-二甲基-2-丁酮和异丙醚混合，在冰浴条件下反应3h，反应结束后进行冷却结晶、离心分离、洗涤、精制和干燥得到辛炔二醇；
(b)按2.5:10:0.02的重量比将辛炔二醇、乙醇和钯催化剂混合，在45℃的温度条件下反应60min，反应过程中持续通入氢气，反应结束后进行分离和提纯得到2,5,6,6-四甲基-2,5-庚二醇，2,5,6,6-四甲基-2,5-庚二醇的结构式如式(Ⅰ)所示；
(1.2)制备掺杂改性的ZrO 2粉体；
(a)将浓度为1.2wt％的Mg(NO 3) 2水溶液与浓度为22wt％的ZrO 2的溶液混合均匀，ZrO 2的溶液的溶剂为硝酸，混合液中Mg 2+与Zr 4+的摩尔比为6:100；
(b)滴加浓度2mol/L的氨水至混合液的pH值为9得到沉淀产物，对沉淀产物进行洗涤和干燥，干燥的温度为106℃，时间为2.5h；
(c)将干燥产物升温至400℃后保温2.5h，然后升温至700℃后保温1.5h，最后在空气中冷却后粉碎得到粒径为0.4微米的掺杂改性的ZrO 2粉体；
(1.3)酯化反应；
对苯二甲酸、乙二醇、2,5,6,6-四甲基-2,5-庚二醇和2,2-二氟-1,5-戊二酸配成浆料，加入掺杂改性的ZrO 2粉体、乙二醇锑、二氧化钛和磷酸三苯酯混合均匀后，在氮气氛围中加压进行酯化反应，加压压力为0.25MPa，酯化反应的温度为250℃，当酯化反应中的水馏出量达到理论值的95％时为酯化反应终点，对苯二甲酸与乙二醇的摩尔比为1:1.4，2,5,6,6-四甲基-2,5-庚二醇和2,2-二氟-1,5-戊二酸的加入量之和为对苯二甲酸加入量的4.6mol％，2,5,6,6-四甲基-2,5-庚二醇和2,2-二氟-1,5-戊二酸的摩尔比为1.5:1，掺杂改性的ZrO 2粉体、乙二醇锑、二氧化钛和磷酸三苯酯的加入量分别为对苯二甲酸加入量的0.24wt％、0.07wt％、3.0wt％和0.01wt％；
(1.4)缩聚反应；
酯化反应结束后，在负压条件下开始低真空阶段的缩聚反应，该阶段压力在35min内由常压平稳抽至绝对压力480Pa，反应温度为258℃，反应时间为45min，然后继续抽真空，进行高真空阶段的缩聚反应，使反应压力进一步降至绝对压力96Pa，反应温度为270℃，反应时间为55min，制得数均分子量为26000，分子量分布指数为1.9的改性聚酯；
(2)制备聚酯FDY丝；
聚酯熔体经计量、喷丝板挤出、冷却、上油、拉伸、热定型和卷绕后制得改性聚酯FDY丝，即得可降解的聚 酯纤维，FDY工艺的参数为：纺丝温度290℃，冷却温度20℃，网络压力0.25MPa，一辊速度2500m/min，一辊温度85℃，二辊速度4000m/min，二辊温度120℃，卷绕速度4000m/min。
可降解的聚酯纤维的单丝纤度为1.5dtex，断裂强度为3.2cN/dtex，断裂伸长率为34％，网络度为14个/m，线密度偏差率为0.8％，断裂强度CV值为4.5％，断裂伸长CV值为8.2％，沸水收缩率为6.3％；
可降解的聚酯纤维在温度为25℃且相对湿度为65％的条件下放置60个月后，其特性粘度下降25％。
实施例5
一种可降解的聚酯纤维的制备方法，步骤如下：
(1)制备改性聚酯；
(1.1)制备2,5,6,6-四甲基-2,5-庚二醇；
(a)按1:1:1.3:3.0的摩尔比将KOH粉末、3-甲基-3-羟基丁炔、3,3-二甲基-2-丁酮和异丙醚混合，在冰浴条件下反应4h，反应结束后进行冷却结晶、离心分离、洗涤、精制和干燥得到辛炔二醇；
(b)按2.5:10:0.02的重量比将辛炔二醇、乙醇和钯催化剂混合，在50℃的温度条件下反应55min，反应过程中持续通入氢气，反应结束后进行分离和提纯得到2,5,6,6-四甲基-2,5-庚二醇，2,5,6,6-四甲基-2,5-庚二醇的结构式如式(Ⅰ)所示；
(1.2)制备掺杂改性的ZrO 2粉体；
(a)将浓度为1.6wt％的LiNO 3水溶液与浓度为24wt％的ZrO 2的溶液混合均匀，ZrO 2的溶液的溶剂为硝酸，混合液中Li +与Zr 4+的摩尔比为7:100；
(b)滴加浓度2mol/L的氨水至混合液的pH值为9～10得到沉淀产物，对沉淀产物进行洗涤和干燥，干燥的温度为110℃，时间为2h；
(c)将干燥产物升温至400℃后保温3h，然后升温至700℃后保温2h，最后在空气中冷却后粉碎得到粒径为0.45微米的掺杂改性的ZrO 2粉体；
(1.3)酯化反应；
对苯二甲酸、乙二醇、2,5,6,6-四甲基-2,5-庚二醇和2,2,3,3-四氟-1,4-丁二酸配成浆料，加入掺杂改性的ZrO 2粉体、醋酸锑、二氧化钛和磷酸三苯酯混合均匀后，在氮气氛围中加压进行酯化反应，加压压力为0.15MPa，酯化反应的温度为260℃，当酯化反应中的水馏出量达到理论值的95％时为酯化反应终点，对苯二甲酸与乙二醇的摩尔比为1:1.5，2,5,6,6-四甲基-2,5-庚二醇和2,2,3,3-四氟-1,4-丁二酸的加入量之和为对苯二甲酸加入量的4.9mol％，2,5,6,6-四甲基-2,5-庚二醇和2,2,3,3-四氟-1,4-丁二酸的摩尔比为1:1.5，掺杂改性的ZrO 2粉体、醋酸锑、二氧化钛和磷酸三苯酯的加入量分别为对苯二甲酸加入量的0.24wt％、0.05wt％、2.0wt％和0.01wt％；
(1.4)缩聚反应；
酯化反应结束后，在负压条件下开始低真空阶段的缩聚反应，该阶段压力在50min内由常压平稳抽至绝对压力480Pa，反应温度为255℃，反应时间为50min，然后继续抽真空，进行高真空阶段的缩聚反应，使反应压力进一步降至绝对压力95Pa，反应温度为282℃，反应时间为80min，制得数均分子量为29000，分子量分布指数为2.1的改性聚酯；
(2)制备聚酯FDY丝；
聚酯熔体经计量、喷丝板挤出、冷却、上油、拉伸、热定型和卷绕后制得改性聚酯FDY丝，即得可降解的聚酯纤维，FDY工艺的参数为：纺丝温度295℃，冷却温度19℃，网络压力0.20MPa，一辊速度2300m/min，一辊温度80℃，二辊速度3800m/min，二辊温度115℃，卷绕速度3730m/min。
可降解的聚酯纤维的单丝纤度为1.5dtex，断裂强度为3.2cN/dtex，断裂伸长率为32％，网络度为12个/m，线密度偏差率为0.9％，断裂强度CV值为4.6％，断裂伸长CV值为8.5％，沸水收缩率为6.5％；
可降解的聚酯纤维在温度为25℃且相对湿度为65％的条件下放置60个月后，其特性粘度下降26％。
实施例6
一种可降解的聚酯纤维的制备方法，步骤如下：
(1)制备改性聚酯；
(1.1)制备2,5,6,6-四甲基-2,5-庚二醇；
(a)按1.1:1:1.2:3.0的摩尔比将KOH粉末、3-甲基-3-羟基丁炔、3,3-二甲基-2-丁酮和异丙醚混合，在冰浴条件下反应4h，反应结束后进行冷却结晶、离心分离、洗涤、精制和干燥得到辛炔二醇；
(b)按3:10:0.03的重量比将辛炔二醇、乙醇和钯催化剂混合，在50℃的温度条件下反应60min，反应过程中持续通入氢气，反应结束后进行分离和提纯得到2,5,6,6-四甲基-2,5-庚二醇，2,5,6,6-四甲基-2,5-庚二醇的结构式如式(Ⅰ)所示；
(1.2)制备掺杂改性的ZrO 2粉体；
(a)将浓度均为2wt％的Mg(NO 3) 2水溶液和Zn(NO 3) 2水溶液按质量比1:1混合得到含金属离子M x+的溶液，将含金属离子M x+的溶液与浓度为20wt％的ZrO 2的溶液混合均匀，ZrO 2的溶液的溶剂为硝酸，混合液中金属离子M x+与Zr 4+的摩尔比为8:100；
(b)滴加浓度2mol/L的氨水至混合液的pH值为10得到沉淀产物，对沉淀产物进行洗涤和干燥，干燥的温度为110℃，时间为2h；
(c)将干燥产物升温至400℃后保温2h，然后升温至700℃后保温1h，最后在空气中冷却后粉碎得到粒径为0.4微米的掺杂改性的ZrO 2粉体；
(1.3)酯化反应；
对苯二甲酸、乙二醇、2,5,6,6-四甲基-2,5-庚二醇和2,2,3,3-四氟-1,4-丁二酸配成浆料，加入掺杂改性的ZrO 2粉体、醋酸锑、二氧化钛和磷酸三苯酯混合均匀后，在氮气氛围中加压进行酯化反应，加压压力为0.3MPa，酯化反应的温度为250℃，当酯化反应中的水馏出量达到理论值的95％时为酯化反应终点，对苯二甲酸与乙二醇的摩尔比为1:1.6，2,5,6,6-四甲基-2,5-庚二醇和2,2,3,3-四氟-1,4-丁二酸的加入量之和为对苯二甲酸加入量的5.2mol％，2,5,6,6-四甲基-2,5-庚二醇和2,2,3,3-四氟-1,4-丁二酸的摩尔比为1.2:1，掺杂改性的ZrO 2粉体、醋酸锑、二氧化钛和磷酸三苯酯的加入量分别为对苯二甲酸加入量的0.25wt％、0.05wt％、2.8wt％和0.01wt％；
(1.4)缩聚反应；
酯化反应结束后，在负压条件下开始低真空阶段的缩聚反应，该阶段压力在30min内由常压平稳抽至绝对压力450Pa，反应温度为260℃，反应时间为30min，然后继续抽真空，进行高真空阶段的缩聚反应，使反应压力进一步降至绝对压力92Pa，反应温度为272℃，反应时间为85min，制得数均分子量为28000，分子量分布指数为1.8的改性聚酯；
(2)制备聚酯FDY丝；
聚酯熔体经计量、喷丝板挤出、冷却、上油、拉伸、热定型和卷绕后制得改性聚酯FDY丝，即得可降解的聚酯纤维，FDY工艺的参数为：纺丝温度295℃，冷却温度19℃，网络压力0.20MPa，一辊速度2300m/min，一辊温度80℃，二辊速度3800m/min，二辊温度115℃，卷绕速度3730m/min。
可降解的聚酯纤维的单丝纤度为1.5dtex，断裂强度为3.2cN/dtex，断裂伸长率为30％，网络度为11个/m，线密度偏差率为1.0％，断裂强度CV值为4.8％，断裂伸长CV值为8.6％，沸水收缩率为6.7％；
可降解的聚酯纤维在温度为25℃且相对湿度为65％的条件下放置60个月后，其特性粘度下降26％。
实施例7
一种可降解的聚酯纤维的制备方法，步骤如下：
(1)制备改性聚酯；
(1.1)制备2,5,6,6-四甲基-2,5-庚二醇；
(a)按1.2:1:1.2:3.0的摩尔比将KOH粉末、3-甲基-3-羟基丁炔、3,3-二甲基-2-丁酮和异丙醚混合，在冰浴条件下反应3h，反应结束后进行冷却结晶、离心分离、洗涤、精制和干燥得到辛炔二醇；
(b)按3:10:0.02的重量比将辛炔二醇、乙醇和钯催化剂混合，在42℃的温度条件下反应55min，反应过程中持续通入氢气，反应结束后进行分离和提纯得到2,5,6,6-四甲基-2,5-庚二醇，2,5,6,6-四甲基-2,5-庚二醇的结构式如式(Ⅰ)所示；
(1.2)制备掺杂改性的ZrO 2粉体；
(a)将浓度均为1wt％的Mg(NO 3) 2水溶液、LiNO 3水溶液和Zn(NO 3) 2水溶液按质量比1:1混合得到含金属离子M x+的溶液，将含金属离子M x+的溶液与浓度为24wt％的ZrO 2的溶液混合均匀，ZrO 2的溶液的溶剂为硝酸，混合液中金属离子M x+与Zr 4+的摩尔比为6:100；
(b)滴加浓度2mol/L的氨水至混合液的pH值为10得到沉淀产物，对沉淀产物进行洗涤和干燥，干燥的温度为110℃，时间为3h；
(c)将干燥产物升温至400℃后保温2h，然后升温至700℃后保温2h，最后在空气中冷却后粉碎得到粒径为0.45微米的掺杂改性的ZrO 2粉体；
(1.3)酯化反应；
对苯二甲酸、乙二醇、2,5,6,6-四甲基-2,5-庚二醇和2,2-二氟-1,3-丙二酸配成浆料，加入掺杂改性的ZrO 2粉体、三氧化二锑、二氧化钛和亚磷酸三甲酯混合均匀后，在氮气氛围中加压进行酯化反应，加压压力为0.2MPa，酯化反应的温度为255℃，当酯化反应中的水馏出量达到理论值的95％时为酯化反应终点，对苯二甲酸与乙二醇的摩尔比为1:1.6，2,5,6,6-四甲基-2,5-庚二醇和2,2-二氟-1,3-丙二酸的加入量之和为对苯二甲酸加入量的5.4mol％，2,5,6,6-四甲基-2,5-庚二醇和2,2-二氟-1,3-丙二酸的摩尔比为2:1.5，掺杂改性的ZrO 2粉体、三氧化二锑、二氧化钛和亚磷酸三甲酯的加入量分别为对苯二甲酸加入量的0.25wt％、0.04wt％、3.0wt％和0.05wt％；
(1.4)缩聚反应；
酯化反应结束后，在负压条件下开始低真空阶段的缩聚反应，该阶段压力在50min内由常压平稳抽至绝对压力490Pa，反应温度为255℃，反应时间为50min，然后继续抽真空，进行高真空阶段的缩聚反应，使反应压力进一步降至绝对压力95Pa，反应温度为275℃，反应时间为55min，制得数均分子量为25000，分子量分布指数为2.2的改性聚酯；
(2)制备聚酯FDY丝；
聚酯熔体经计量、喷丝板挤出、冷却、上油、拉伸、热定型和卷绕后制得改性聚酯FDY丝，即得可降解的聚酯纤维，FDY工艺的参数为：纺丝温度285℃，冷却温度22℃，网络压力0.30MPa，一辊速度2700m/min，一辊温度90℃，二辊速度4200m/min，二辊温度130℃，卷绕速度4120m/min。
可降解的聚酯纤维的单丝纤度为1.0dtex，断裂强度为3.1cN/dtex，断裂伸长率为30％，网络度为15个/m，线密度偏差率为1.0％，断裂强度CV值为4.7％，断裂伸长CV值为8.8％，沸水收缩率为6.8％；
可降解的聚酯纤维在温度为25℃且相对湿度为65％的条件下放置60个月后，其特性粘度下降27％。
实施例8
一种可降解的聚酯纤维的制备方法，步骤如下：
(1)制备改性聚酯；
(1.1)制备2,5,6,6-四甲基-2,5-庚二醇；
(a)按1.2:1:1.2:3.0的摩尔比将KOH粉末、3-甲基-3-羟基丁炔、3,3-二甲基-2-丁酮和异丙醚混合，在冰浴条件下反应3h，反应结束后进行冷却结晶、离心分离、洗涤、精制和干燥得到辛炔二醇；
(b)按3:10:0.02的重量比将辛炔二醇、乙醇和钯催化剂混合，在42℃的温度条件下反应55min，反应过程中持续通入氢气，反应结束后进行分离和提纯得到2,5,6,6-四甲基-2,5-庚二醇，2,5,6,6-四甲基-2,5-庚二醇的结构式如式(Ⅰ)所示；
(1.2)制备掺杂改性的ZrO 2粉体；
(a)将浓度均为1wt％的Mg(NO 3) 2水溶液、LiNO 3水溶液和Zn(NO 3) 2水溶液按质量比1:1混合得到含金属离子M x+的溶液，将含金属离子M x+的溶液与浓度为24wt％的ZrO 2的溶液混合均匀，ZrO 2的溶液的溶剂为硝酸，混合液中金属离子M x+与Zr 4+的摩尔比为6:100；
(b)滴加浓度2mol/L的氨水至混合液的pH值为10得到沉淀产物，对沉淀产物进行洗涤和干燥，干燥的温度为110℃，时间为3h；
(c)将干燥产物升温至400℃后保温2h，然后升温至700℃后保温2h，最后在空气中冷却后粉碎得到粒径为0.45微米的掺杂改性的ZrO 2粉体；
(1.3)酯化反应；
对苯二甲酸、乙二醇、2,5,6,6-四甲基-2,5-庚二醇和2,2-二氟-1,3-丙二酸配成浆料，加入掺杂改性的ZrO 2粉体、乙二醇锑、二氧化钛和磷酸三苯酯混合均匀后，在氮气氛围中加压进行酯化反应，加压压力为0.3MPa，酯化反应的温度为255℃，当酯化反应中的水馏出量达到理论值的95％时为酯化反应终点，对苯二甲酸与乙二醇的摩尔比为1:2.0，2,5,6,6-四甲基-2,5-庚二醇和2,2-二氟-1,3-丙二酸的加入量之和为对苯二甲酸加入量的5.8mol％，2,5,6,6-四甲 基-2,5-庚二醇和2,2-二氟-1,3-丙二酸的摩尔比为2:1，掺杂改性的ZrO 2粉体、乙二醇锑、二氧化钛和磷酸三苯酯的加入量分别为对苯二甲酸加入量的0.25wt％、0.04wt％、2.0wt％和0.03wt％；
(1.4)缩聚反应；
酯化反应结束后，在负压条件下开始低真空阶段的缩聚反应，该阶段压力在50min内由常压平稳抽至绝对压力480Pa，反应温度为260℃，反应时间为40min，然后继续抽真空，进行高真空阶段的缩聚反应，使反应压力进一步降至绝对压力95Pa，反应温度为272℃，反应时间为90min，制得数均分子量为29000，分子量分布指数为2.1的改性聚酯；
(2)制备聚酯FDY丝；
聚酯熔体经计量、喷丝板挤出、冷却、上油、拉伸、热定型和卷绕后制得改性聚酯FDY丝，即得可降解的聚酯纤维，FDY工艺的参数为：纺丝温度285℃，冷却温度22℃，网络压力0.30MPa，一辊速度2700m/min，一辊温度90℃，二辊速度4200m/min，二辊温度130℃，卷绕速度4120m/min。
可降解的聚酯纤维的单丝纤度为1.0dtex，断裂强度为3.0cN/dtex，断裂伸长率为29％，网络度为11个/m，线密度偏差率为1.0％，断裂强度CV值为5.0％，断裂伸长CV值为8.8％，沸水收缩率为7.0％；
可降解的聚酯纤维在温度为25℃且相对湿度为65％的条件下放置60个月后，其特性粘度下降28％。

Claims (10)

  1. 可降解的聚酯纤维的制备方法，其特征是：按FDY工艺由改性聚酯熔体制得改性聚酯FDY丝，即得可降解的聚酯纤维；
    所述改性聚酯的制备方法为：将对苯二甲酸、乙二醇、2,5,6,6-四甲基-2,5-庚二醇、含氟二元酸和掺杂改性的ZrO 2粉体混合均匀后先后进行酯化反应和缩聚反应；
    2,5,6,6-四甲基-2,5-庚二醇的结构式如下：
    Figure PCTCN2019113873-appb-100001
    含氟二元酸为2,2-二氟-1,3-丙二酸、2,2-二氟-1,4-丁二酸、2,2-二氟-1,5-戊二酸或2,2,3,3-四氟-1,4-丁二酸；
    ZrO 2掺杂改性的过程为：首先将含金属离子M x+的溶液与含Zr 4+的溶液混合均匀，然后滴加沉淀剂至混合液的pH值为9～10，最后煅烧沉淀产物；金属离子M x+为Mg 2+、Li +和Zn 2+中的一种以上。
  2. 根据权利要求1所述的可降解的聚酯纤维的制备方法，其特征在于，所述2,5,6,6-四甲基-2,5-庚二醇的合成步骤如下：
    (1)按1～1.2:1:1.2～1.3:2.0～3.0的摩尔比将KOH粉末、3-甲基-3-羟基丁炔、3,3-二甲基-2-丁酮和异丙醚混合，在冰浴条件下反应2～4h，反应结束后进行冷却结晶、离心分离、洗涤、精制和干燥得到辛炔二醇；
    (2)按2～3:10:0.01～0.03的重量比将辛炔二醇、乙醇和钯催化剂混合，在40～50℃的温度条件下反应50～60min，反应过程中持续通入氢气，反应结束后进行分离和提纯得到2,5,6,6-四甲基-2,5-庚二醇。
  3. 根据权利要求2所述的可降解的聚酯纤维的制备方法，其特征在于，所述含金属离子M x+的溶液的浓度为1～2wt％，溶剂为水，溶液中的阴离子为NO 3 -；所述含Zr 4+的溶液为浓度20～25wt％的ZrO 2的溶液，溶剂为硝酸；所述沉淀剂为浓度2mol/L的氨水；沉淀开始时，混合液中金属离子M x+与Zr 4+的摩尔比为5～8:100；
    所述煅烧前对沉淀产物进行洗涤和干燥，干燥的温度为105～110℃，时间为2～3h；所述煅烧的过程为：首先升温至400℃后保温2～3h，然后升温至 700℃后保温1～2h，最后在空气中冷却；ZrO 2在掺杂改性后进行粉碎得到平均粒径小于0.5微米的粉体。
  4. 根据权利要求3所述的可降解的聚酯纤维的制备方法，其特征在于，所述改性聚酯的制备步骤如下：
    (1)酯化反应；
    将对苯二甲酸、乙二醇、2,5,6,6-四甲基-2,5-庚二醇和含氟二元酸配成浆料，加入掺杂改性的ZrO 2粉体、催化剂、消光剂和稳定剂混合均匀后，在氮气氛围中加压进行酯化反应，加压压力为常压～0.3MPa，酯化反应的温度为250～260℃，当酯化反应中的水馏出量达到理论值的90％以上时为酯化反应终点；
    (2)缩聚反应；
    酯化反应结束后，在负压条件下开始低真空阶段的缩聚反应，该阶段压力在30～50min内由常压平稳抽至绝对压力500Pa以下，反应温度为250～260℃，反应时间为30～50min，然后继续抽真空，进行高真空阶段的缩聚反应，使反应压力进一步降至绝对压力100Pa以下，反应温度为270～282℃，反应时间为50～90min。
  5. 根据权利要求4所述的可降解的聚酯纤维的制备方法，其特征在于，所述对苯二甲酸与乙二醇的摩尔比为1:1.2～2.0，所述2,5,6,6-四甲基-2,5-庚二醇和含氟二元酸的加入量之和为对苯二甲酸加入量的4～6mol％，所述2,5,6,6-四甲基-2,5-庚二醇与含氟二元酸的摩尔比为1～2:1～2，所述掺杂改性的ZrO 2粉体、催化剂、消光剂和稳定剂的加入量分别为对苯二甲酸加入量的0.23～0.25wt％、0.03～0.05wt％、0.20～0.25wt％和0.01～0.05wt％。
  6. 根据权利要求5所述的可降解的聚酯纤维的制备方法，其特征在于，所述催化剂为三氧化二锑、乙二醇锑或醋酸锑，所述消光剂为二氧化钛，所述稳定剂为磷酸三苯酯、磷酸三甲酯或亚磷酸三甲酯。
  7. 根据权利要求6所述的可降解的聚酯纤维的制备方法，其特征在于，改性聚酯的数均分子量为25000～30000，分子量分布指数为1.8～2.2。
  8. 根据权利要求1所述的可降解的聚酯纤维的制备方法，其特征在于，所述FDY工艺的流程为：计量、喷丝板挤出、冷却、上油、拉伸、热定型和卷绕；
    所述FDY工艺的参数为：纺丝温度285～295℃，冷却温度19～22℃，网络压力0.20～0.30MPa，一辊速度2300～2700m/min，一辊温度80～90℃，二辊速度3800～4200m/min，二辊温度115～130℃，卷绕速度3730～4120m/min。
  9. 采用如权利要求1～8任一项所述的可降解的聚酯纤维的制备方法制得的可降解的聚酯纤维，其特征是：为改性聚酯FDY丝；
    所述改性聚酯的分子链包括对苯二甲酸链段、乙二醇链段、2,5,6,6-四甲基-2,5-庚二醇链段和含氟二元酸链段；
    所述改性聚酯中分散有掺杂改性的ZrO 2粉体；掺杂改性的过程为：首先将含金属离子M x+的溶液与含Zr 4+的溶液混合均匀，然后滴加沉淀剂至混合液的pH值为9～10，最后煅烧沉淀产物；金属离子M x+为Mg 2+、Li +和Zn 2+中的一种以上。
  10. 根据权利要求9所述的可降解的聚酯纤维，其特征在于，可降解的聚酯纤维的单丝纤度为1.0～2.0dtex，断裂强度≥3.0cN/dtex，断裂伸长率为32.0±4.0％，网络度为13±2个/m，线密度偏差率≤1.0％，断裂强度CV值≤5.0％，断裂伸长CV值≤9.0％，沸水收缩率为6.5±0.5％；可降解的聚酯纤维在温度为25℃且相对湿度为65％的条件下放置60个月后，其特性粘度下降23～28％。
PCT/CN2019/113873 2018-12-27 2019-10-29 可降解的聚酯纤维及其制备方法 WO2020134498A1 (zh)

Priority Applications (3)

Application Number Priority Date Filing Date Title
US17/277,306 US11174345B2 (en) 2018-12-27 2019-10-29 Degradable polyester fiber and preparing method thereof
JP2021533240A JP7053960B2 (ja) 2018-12-27 2019-10-29 生分解可能なポリエステル繊維の製造方法
EP19905717.5A EP3842577B1 (en) 2018-12-27 2019-10-29 Degradable polyester fiber and preparation method therefor

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201811615787.7 2018-12-27
CN201811615787.7A CN109722740B (zh) 2018-12-27 2018-12-27 可降解的聚酯纤维及其制备方法

Publications (1)

Publication Number Publication Date
WO2020134498A1 true WO2020134498A1 (zh) 2020-07-02

Family

ID=66296567

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2019/113873 WO2020134498A1 (zh) 2018-12-27 2019-10-29 可降解的聚酯纤维及其制备方法

Country Status (5)

Country Link
US (1) US11174345B2 (zh)
EP (1) EP3842577B1 (zh)
JP (1) JP7053960B2 (zh)
CN (1) CN109722740B (zh)
WO (1) WO2020134498A1 (zh)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109722740B (zh) * 2018-12-27 2020-10-16 江苏恒力化纤股份有限公司 可降解的聚酯纤维及其制备方法
CN111118650B (zh) 2019-12-29 2021-08-13 江苏恒力化纤股份有限公司 一种可降解聚酯纤维及其制备方法
CN117924680B (zh) * 2024-01-26 2024-06-21 江苏贝尔特福新材料股份有限公司 一种可降解涤纶针织布及制备工艺

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1119836A (zh) * 1993-12-22 1996-04-03 花王株式会社 烷氧基化催化剂和其制法及用其制备烷氧基化物的方法
CN1247181A (zh) * 1999-08-25 2000-03-15 成都惟精防水材料研究所 2,5－二甲基－2,5－己二醇一步合成法
US20120322714A1 (en) * 2011-06-15 2012-12-20 Basf Se Branched polyesters with sulfonate groups
CN106367835A (zh) * 2016-08-31 2017-02-01 江苏恒力化纤股份有限公司 一种聚酯纤维及其制备方法
CN106801265A (zh) * 2016-12-29 2017-06-06 江苏恒科新材料有限公司 一种8字中空形聚酯纤维fdy丝及其制备方法
CN109722740A (zh) * 2018-12-27 2019-05-07 江苏恒力化纤股份有限公司 可降解的聚酯纤维及其制备方法

Family Cites Families (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4502976A (en) * 1982-10-25 1985-03-05 Bend Research, Inc. Water soluble polyesters
CN101781805A (zh) * 2010-02-03 2010-07-21 东华大学 生物可降解共聚酯全牵伸丝的一步法制备方法
CN106245149B (zh) * 2016-08-31 2018-09-14 江苏恒力化纤股份有限公司 一种高均匀性车模聚酯工业丝及其制备方法
CN106283251B (zh) * 2016-08-31 2018-05-18 江苏恒力化纤股份有限公司 一种多孔ptt纤维hoy丝及其制备方法
CN106381557B (zh) * 2016-08-31 2018-07-27 江苏恒力化纤股份有限公司 一种高均匀性安全带用聚酯工业丝及其制备方法
CN108385186B (zh) * 2017-12-14 2020-04-17 江苏恒力化纤股份有限公司 一种聚酯poy纤维及其制备方法
CN108130624B (zh) * 2017-12-14 2020-05-05 江苏恒力化纤股份有限公司 一种聚酯仿麻型异收缩复合丝及其制备方法
CN108385194B (zh) * 2017-12-14 2019-12-24 江苏恒力化纤股份有限公司 一种染性聚酯fdy纤维及其制备方法
CN108071009B (zh) * 2017-12-14 2020-07-07 江苏恒力化纤股份有限公司 一种减少涤纶纱线毛羽的方法
CN108660538A (zh) * 2018-06-08 2018-10-16 佛山市南海区佳妍内衣有限公司 一种抗菌型多功能聚酯纤维
CN109735939B (zh) * 2018-12-27 2020-10-16 江苏恒力化纤股份有限公司 熔体直纺在线添加有色聚酯纤维及其制备方法
CN109735930B (zh) * 2018-12-27 2020-10-16 江苏恒力化纤股份有限公司 全消光涤纶牵伸丝及其制备方法
CN109722738B (zh) * 2018-12-27 2020-07-07 江苏恒力化纤股份有限公司 半消光涤纶牵伸丝及其制备方法
CN109750379B (zh) * 2018-12-27 2020-10-16 江苏恒力化纤股份有限公司 超亮光涤纶低弹丝及其制备方法
CN109735927B (zh) * 2018-12-27 2020-10-16 江苏恒力化纤股份有限公司 全消光涤纶低弹丝及其制备方法

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1119836A (zh) * 1993-12-22 1996-04-03 花王株式会社 烷氧基化催化剂和其制法及用其制备烷氧基化物的方法
CN1247181A (zh) * 1999-08-25 2000-03-15 成都惟精防水材料研究所 2,5－二甲基－2,5－己二醇一步合成法
US20120322714A1 (en) * 2011-06-15 2012-12-20 Basf Se Branched polyesters with sulfonate groups
CN106367835A (zh) * 2016-08-31 2017-02-01 江苏恒力化纤股份有限公司 一种聚酯纤维及其制备方法
CN106801265A (zh) * 2016-12-29 2017-06-06 江苏恒科新材料有限公司 一种8字中空形聚酯纤维fdy丝及其制备方法
CN109722740A (zh) * 2018-12-27 2019-05-07 江苏恒力化纤股份有限公司 可降解的聚酯纤维及其制备方法

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP3842577A4 *

Also Published As

Publication number Publication date
CN109722740B (zh) 2020-10-16
US11174345B2 (en) 2021-11-16
JP2022511950A (ja) 2022-02-01
JP7053960B2 (ja) 2022-04-12
CN109722740A (zh) 2019-05-07
EP3842577B1 (en) 2022-12-07
US20210284792A1 (en) 2021-09-16
EP3842577A1 (en) 2021-06-30
EP3842577A4 (en) 2022-01-19

Similar Documents

Publication Publication Date Title
WO2020134498A1 (zh) 可降解的聚酯纤维及其制备方法
CN109735930B (zh) 全消光涤纶牵伸丝及其制备方法
US11248087B2 (en) Cationic dyeable polyester fiber and preparing method thereof
CN109706542B (zh) 一种阻燃聚酯纤维及其制备方法
CN107413325B (zh) 一种稀土/碳共掺杂柔性TiO2纳米纤维膜及其制备方法
CN109505026B (zh) 吸湿排汗涤纶纤维及其制备方法
WO2020134497A1 (zh) 易染多孔改性聚酯纤维及其制备方法
CN109706541B (zh) 医用织物用纤维及其制备方法
WO2020134494A1 (zh) 半消光涤纶牵伸丝及其制备方法
JP7059450B2 (ja) 染色、生分解しやすいポリエステルｆｄｙ糸及びその製造方法
CN109721751A (zh) 聚酯薄膜及其制备方法
CN109735927B (zh) 全消光涤纶低弹丝及其制备方法
CN109750375B (zh) 一种轻量化保暖纤维及其制备方法
CN109722736B (zh) 一种含氟二元酸改性聚酯fdy纤维及其制备方法
CN109666984B (zh) 一种含固体杂多酸的改性聚酯poy纤维及其制备方法
CN109722737B (zh) 一种含有固体碱催化剂的改性聚酯纤维及其制备方法
WO2021135079A1 (zh) 一种可降解聚酯纤维及其制备方法
CN109680362B (zh) 涤锦皮芯复合丝及其制备方法
CN109666986B (zh) 一种易染聚酯fdy纤维及其制备方法
CN109680357B (zh) 有光黑色涤纶长丝及其制备方法
CN109666981B (zh) 涤纶多孔丝及其制备方法
CN109853082B (zh) 皮芯热熔丝及其制备方法
CN109750374B (zh) 半消光涤纶低弹丝及其制备方法
CN109722730B (zh) 半消光涤纶预取向丝及其制备方法

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 19905717

Country of ref document: EP

Kind code of ref document: A1

ENP Entry into the national phase

Ref document number: 2019905717

Country of ref document: EP

Effective date: 20210323

ENP Entry into the national phase

Ref document number: 2021533240

Country of ref document: JP

Kind code of ref document: A

NENP Non-entry into the national phase

Ref country code: DE