CN111519272A - Preparation method of low-melting-point copolyester polylactic acid fiber - Google Patents

Preparation method of low-melting-point copolyester polylactic acid fiber Download PDF

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CN111519272A
CN111519272A CN202010601860.6A CN202010601860A CN111519272A CN 111519272 A CN111519272 A CN 111519272A CN 202010601860 A CN202010601860 A CN 202010601860A CN 111519272 A CN111519272 A CN 111519272A
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polylactic acid
copolyester
fiber
melting
temperature
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樊海彬
任杰
李文俊
谢鹏飞
张志刚
龚家颖
宋晓平
王志梅
符敏初
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SUZHOU KINGCHARM NEW MATERIALS CORP
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    • DTEXTILES; PAPER
    • D01NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
    • D01FCHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
    • D01F6/00Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof
    • D01F6/78Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from copolycondensation products
    • D01F6/84Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from copolycondensation products from copolyesters
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08GMACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G63/00Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
    • C08G63/02Polyesters derived from hydroxycarboxylic acids or from polycarboxylic acids and polyhydroxy compounds
    • C08G63/06Polyesters derived from hydroxycarboxylic acids or from polycarboxylic acids and polyhydroxy compounds derived from hydroxycarboxylic acids
    • C08G63/08Lactones or lactides
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08GMACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G63/00Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
    • C08G63/78Preparation processes
    • C08G63/82Preparation processes characterised by the catalyst used
    • C08G63/85Germanium, tin, lead, arsenic, antimony, bismuth, titanium, zirconium, hafnium, vanadium, niobium, tantalum, or compounds thereof
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08GMACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G63/00Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
    • C08G63/91Polymers modified by chemical after-treatment
    • C08G63/912Polymers modified by chemical after-treatment derived from hydroxycarboxylic acids

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  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Health & Medical Sciences (AREA)
  • Medicinal Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Organic Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Textile Engineering (AREA)
  • Polyesters Or Polycarbonates (AREA)
  • Polyurethanes Or Polyureas (AREA)

Abstract

A preparation method of a low-melting-point copolyester polylactic acid fiber relates to the technical field of polylactic acid fiber preparation. The method comprises the following steps: firstly, preparing copolyester fiber master batches through three steps of lactic acid self-polymerization, lactic acid oligomer and polycaprolactone diol copolymerization and melt chain extension, and then drying the copolyester fiber master batches and carrying out melt spinning to obtain the low-melting-point copolyester polylactic acid fiber. The characteristics of good toughness and low melting point of PCL are utilized to modify polylactic acid, so that the fiber toughness is improved, the melting point of the spinning master batch is reduced, and the processing temperature is reduced, thereby reducing the influence of high temperature on the degradation of the polylactic acid and improving the mechanical property of the fiber; under the conditions of the preferable raw material components, specific process parameters and the like, the molecular weight of the copolyester polylactic acid is increased through the chain extension of diisocyanate and butanediol on the prepolymer, so that the molecular weight required by spinning is achieved; has environment-friendly performance and good application prospect.

Description

Preparation method of low-melting-point copolyester polylactic acid fiber
Technical Field
The invention relates to the technical field of polylactic acid fiber preparation, in particular to a preparation method of a low-melting-point copolyester polylactic acid fiber.
Background
Polylactic acid (PLA) fiber mainly uses natural renewable resources as raw materials, reduces the dependence on non-renewable resources such as petroleum, and has excellent mechanical properties and degradability. With the increasing attention of people to the environment, the scale and cost reduction of PLA synthesis and the continuous expansion of the application field, the PLA fiber is bound to become one of important fiber varieties and is expected to replace the traditional chemical fiber materials such as polypropylene fiber, terylene, chinlon and the like in many fields.
In the field of synthetic fibers, sheath-core structured composite fibers have been widely used in the manufacture of through-air nonwovens, wherein a low melting sheath layer is heated to act as a binder and provide the material with its overall special properties, while a higher melting core layer provides the main mechanical strength. The excellent mechanical property of the polylactic acid is not transferred to the traditional petroleum-based materials such as PP and PET, and simultaneously, the polylactic acid has excellent biodegradable property, so that the polylactic acid has great potential in the field of composite fibers. However, PLA has poor compatibility with petroleum-based polymers and a large difference in melting point with bio-based polymers, which causes many problems in the actual production process of composite fibers. With the reduction in production of low melting PLA of Natureworks, usa, the difficulty of preparing low melting PLA/normal melting PLA composite fibers of sheath-core structure has increased. Therefore, it is required to prepare a low melting point polylactic acid.
The invention patent of China with application publication number CN108359087A describes 'a low-melting-point branched polylactic acid and a preparation method thereof', the method comprises the steps of carrying out melt blending reaction on polylactic acid, Lewis acid and trifunctional acrylate monomers in different proportions in a screw extruder, reducing the crystallinity of the polylactic acid through the combined action of the Lewis acid and the acrylate monomers, enabling the polylactic acid to generate branching and be degraded, and reducing the molecular weight of the polylactic acid, thereby reducing the melting point. The spinnability of the polylactic acid prepared by the method is greatly influenced along with the reduction of molecular weight and the increase of branched chains. And thus cannot be applied to the field of fibers.
Chinese patent publication No. CN102010583A describes "a polymeric long-chain branched crystalline polylactic acid material and a method for preparing the same", in which protonic acid is added to an aqueous solution of lactic acid as a catalyst, dehydration is performed, then dibasic acid or acid anhydride is added to obtain a product, and then a lewis acid catalyst is used for a polycondensation reaction, and diglycidyl ester is added as a crystallization promoter, to finally obtain long-chain branched crystalline polylactic acid. However, the small molecule diglycidyl ester migrates to the surface of the product, eventually making the product unstable.
The existing method for lowering the melting point of the polylactic acid is to perform branching treatment on the polylactic acid, but basically the crystallinity of the polylactic acid after the branching treatment is reduced, and finally the spinnability is reduced. Therefore, it is of positive interest to explore how to prepare low melting polylactic acid with good spinnability without substantially affecting crystallinity, and the technical solutions described below are made in this context.
Disclosure of Invention
The invention aims to overcome the defects in the prior art and provide a preparation method of a low-melting-point copolyester polylactic acid fiber.
The invention aims to achieve the aim that the preparation method of the low-melting-point copolyester polylactic acid fiber comprises the following steps:
firstly, preparing copolyester fiber master batches through three steps of lactic acid self-polymerization, lactic acid oligomer and polycaprolactone diol copolymerization and melt chain extension, and then drying the copolyester fiber master batches and carrying out melt spinning to obtain the low-melting-point copolyester polylactic acid fiber.
In a specific embodiment of the present invention, the copolyester fiber masterbatch comprises the following components in parts by weight:
70-90 parts of L-LA;
10-30 parts of PCL-OH;
0.1-0.2 part of catalyst;
1-3 parts of a micromolecular chain extender;
the purity of the L-LA is 88-98%;
the catalyst is a mixed solution of stannous octoate and toluene.
In another specific embodiment of the present invention, the small molecule chain extender is a mixture of diisocyanate (HDI) and Butanediol (BDO).
In another embodiment of the present invention, the conditions of the lactic acid self-polymerization process are as follows: the vacuum degree is 1000Pa, the magnetic stirring is carried out, the reaction starting temperature is 80-100 ℃, the constant temperature is kept to rise to 175 ℃ of 165-plus-material temperature, the temperature rising rate is 8-12 ℃/min, the catalyst is added at 120 ℃ of 100-plus-material temperature, and the whole reaction time is kept for 16-20 h.
In another specific embodiment of the present invention, the copolymerization process conditions of the lactic acid oligomer and the polycaprolactone diol are as follows: the vacuum degree is 1000Pa, magnetic stirring is carried out, PCL-OH is added, and the reaction is kept for 5-7h at the temperature of 155-175 ℃.
In yet another specific embodiment of the present invention, the conditions of the melt chain extension process are as follows: the preparation method is carried out in a Haake internal mixer, the rotating speed of a rotor is 60-100rpm, a micromolecular chain extender is dropwise added, the reaction temperature is set to 155-.
In a more specific embodiment of the present invention, the melt spinning conditions are a spinning temperature of 190-.
In a further specific embodiment of the present invention, the drying temperature of the copolyester fiber master batch is 100-110 ℃, and the drying time is 20-24 h.
In yet a more particular embodiment of the invention, the low melting copolyester polylactic acid fiber has a monofilament linear density of 2.1 to 2.4dtex, a breaking strength of 3.4 to 3.8CN/dtex, and an elongation at break of 28 to 32%.
The technical scheme provided by the invention has the technical effects that: compared with the prior art, the PCL chain segment is connected on the PLA to form the copolymer through the copolymerization reaction of the lactic acid oligomer and the polycaprolactone diol, the polylactic acid is reformed by utilizing the characteristics of good toughness and low melting point of the PCL, the fiber toughness is improved, the melting point of the spinning master batch is reduced, the processing temperature is reduced, the influence of high temperature on the degradation of the polylactic acid is reduced, and the mechanical property of the fiber is improved. Under the conditions of the preferable raw material components, specific process parameters and the like, the molecular weight of the copolyester polylactic acid is increased through the chain extension of the diisocyanate and the butanediol and the prepolymer, so that the molecular weight required by spinning is achieved. Because PCL is a biodegradable material, the fiber prepared from the copolymerization modified polylactic acid material has environment-friendly performance and good application prospect.
Detailed Description
The disclosure may be understood more readily by reference to the following detailed description of preferred embodiments of the invention and the examples included therein. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. In case of conflict, the present specification, including definitions, will control.
The terms "comprises" or "comprising," or any other variation thereof, as used herein, are intended to cover a non-exclusive inclusion. For example, a composition, process, method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such composition, process, method, article, or apparatus.
When an amount, concentration, or other value or parameter is expressed as a range, preferred range, or as a range of upper preferable values and lower preferable values, this is to be understood as specifically disclosing all ranges formed from any pair of any upper range limit or preferred value and any lower range limit or preferred value, regardless of whether ranges are separately disclosed. For example, when a range of "1 to 5" is disclosed, the described range should be interpreted to include the ranges "1 to 4", "1 to 3", "1 to 2 and 4 to 5", "1 to 3 and 5", and the like. When a range of values is described herein, unless otherwise stated, the range is intended to include the endpoints thereof and all integers and fractions within the range.
Approximating language, as used herein in the specification and claims, may be applied to modify a quantity, such that the invention is not limited to the specific value, but includes equivalents thereof, as modified in response to specific variations thereof without departing from the basic function to which the invention is related. Accordingly, the use of "about" to modify a numerical value means that the invention is not limited to the precise value. In some instances, the approximating language may correspond to the precision of an instrument for measuring the value. In the present description and claims, range limitations may be combined and/or interchanged, including all sub-ranges contained therein if not otherwise stated.
In addition, the indefinite articles "a" and "an" preceding an element or component of the invention are not intended to limit the number requirement (i.e., the number of occurrences) of the element or component. Thus, "a" or "an" should be read to include one or at least one, and the singular form of an element or component also includes the plural unless the stated number clearly indicates that the singular form is intended.
The present invention will be described in detail with reference to specific comparative examples and examples.
The invention uses the following raw material sources: l-lactic acid (Tongjielian biomaterial, Inc. in Suzhou, Jiangsu, China), polycaprolactone diol (either commercially available or available by the manufacturer);
comparative example 1:
vacuum drying the polylactic acid slices at 110 ℃ for 16h, then adding the dried slices into a spinning machine, wherein the spinning temperature is 230 ℃, and the winding speed is 1800 m/min; the drafting temperature is set to be 100 ℃, and the drafting multiple is 4 times, so that the polylactic acid fiber is finally obtained.
The obtained polylactic acid fiber monofilament has the linear density of 1.5dtex, the breaking strength of 4.2cN/dtex and the elongation at break of 6.1 percent; the fiber has obvious melting peak near 180 ℃ measured by Differential Scanning Calorimetry (DSC). The fiber surface is smooth and flat. Comparative example 1 is some of the properties of a pure polylactic acid fiber, which can be compared with the examples that follow.
Example 1:
putting 70 parts of L-lactic acid (namely L-LA, the same below) with the purity of 98 percent weighed according to the parts by weight into a three-mouth flask, keeping the vacuum degree of the flask at 1000Pa, adding the L-lactic acid into a magnetic stirring device (the same below) through magnetic stirring, keeping the reaction starting temperature at 80 ℃, keeping the heating rate of 10 ℃/h, heating the L-lactic acid to 170 ℃, adding 0.1 part of stannous octoate and toluene mixed solution weighed according to the parts by weight at the temperature of 110 ℃ as a catalyst, keeping the whole reaction process for 16 hours, and finally obtaining a lactic acid oligomer; then adding 20 parts of PCL-OH weighed according to parts by weight into the lactic acid oligomer, keeping the vacuum degree of 1000Pa, stirring by magnetic force, and reacting at 165 ℃ for 6 hours to obtain the PLA-PCL copolymer prepolymer. Adding the obtained PLA-PCL copolymer prepolymer into a Haake internal mixer, setting the rotating speed at 80rpm, setting the temperature at 165 ℃ and setting the time at 18min, dropwise adding 3 parts of a mixture of diisocyanate (HDI) and Butanediol (BDO) or serving as a small molecular chain extender, which is weighed according to parts by weight, in the internal mixing process of the Haake internal mixer for 18min, and finally obtaining copolymerization modified polylactic acid master batches to obtain copolyester fiber master batches;
drying the copolyester fiber master batch at 100 ℃ for 24 hours, and then adding the copolyester fiber master batch into a spinning machine, wherein the spinning temperature is 215 ℃, and the winding speed is 1400 m/min; the drawing temperature was set to 90 ℃ and the drawing ratio (also referred to as "draw ratio", hereinafter) was 3.1 times, to finally obtain a low-melting-point copolyester polylactic acid fiber.
The successful synthesis of the obtained copolymerized master batch can be known through nuclear magnetism and infrared spectra. The monofilament linear density of the low-melting-point copolyester polylactic acid fiber is 2.4dtex, the breaking strength is 3.4 cN/dtex, and the elongation at break is 32%. Compared with the comparative example, the copolymer has the advantages that the toughness is improved, but the tensile strength is slightly reduced, and the melting point is slightly reduced compared with the pure polylactic acid.
Example 2:
putting 90 parts of L-lactic acid with the purity of 88 percent weighed according to the parts by weight into a three-neck flask, keeping the vacuum degree of the flask at 1000Pa, adding magnetic stirring, keeping the reaction starting temperature at 100 ℃, keeping the heating rate of 12 ℃/h, heating to 165 ℃, adding 0.15 part of stannous octoate and toluene mixed solution weighed according to the parts by weight as a catalyst at the temperature of 115 ℃, keeping the whole reaction process for 18 hours, and finally obtaining a lactic acid oligomer; then adding 10 parts of PCL-OH weighed according to parts by weight into the lactic acid oligomer, keeping the vacuum degree of 1000Pa, stirring by magnetic force, and reacting at 155 ℃ for 7 hours to obtain the PLA-PCL copolymer prepolymer. Adding the obtained PLA-PCL copolymer prepolymer into a Haake internal mixer, setting the rotating speed at 60rpm, setting the temperature at 175 ℃, and keeping the time for 15min, dropwise adding 1 part of a small molecular chain extender which is formed by a mixture of diisocyanate (HDI) and Butanediol (BDO) or called serving as the mixture and is weighed according to parts by weight in the 15min internal mixing process of the Haake internal mixer, and finally obtaining copolymerization modified polylactic acid master batches to obtain copolyester fiber master batches;
drying the copolyester fiber master batch at 110 ℃ for 20 hours, and then adding the dried master batch into a spinning machine, wherein the spinning temperature is 190 ℃, and the winding speed is 1000 m/min; the drafting temperature is set to 85 ℃, and the drafting multiple is 2.5 times, so that the low-melting-point copolyester polylactic acid fiber is finally obtained.
The successful synthesis of the obtained copolymerized master batch can be known through nuclear magnetism and infrared spectra. The low melting point copolyester polylactic acid fiber monofilament has the linear density of 2.2dtex, the breaking strength of 3.5 cN/dtex and the elongation at break of 30 percent. The fiber has an obvious melting peak near 167 ℃ measured by Differential Scanning Calorimetry (DSC), and the surface appearance of the fiber is smooth measured under a scanning electron microscope.
Example 3:
and (2) putting 80 parts of L-lactic acid with the purity of 92 percent weighed according to the parts by weight into a three-neck flask, keeping the vacuum degree of the flask at 1000Pa, adding magnetic stirring, keeping the reaction starting temperature at 90 ℃, keeping the heating rate of 8 ℃/h, heating to 175 ℃, adding 0.2 part of stannous octoate and toluene mixed solution weighed according to the parts by weight as a catalyst at the temperature of 120 ℃, keeping the whole reaction process for 17 hours, and finally obtaining the lactic acid oligomer. Then adding 30 parts of PCL-OH weighed according to parts by weight into the lactic acid oligomer, keeping the vacuum degree of 1000Pa, stirring by magnetic force, and reacting at 170 ℃ for 5 hours to obtain the PLA-PCL copolymer prepolymer. Adding the obtained PLA-PCL copolymer prepolymer into a Haake internal mixer, setting the rotating speed at 100rpm, setting the temperature at 155 ℃, setting the time at 20min, dropwise adding 2 parts of a mixture of diisocyanate (HDI) and Butanediol (BDO) or serving as a small molecular chain extender which is weighed according to parts by weight in the internal mixing process of the Haake internal mixer for 20min, and finally obtaining copolymerization modified polylactic acid master batches to obtain copolyester fiber master batches;
drying the copolyester fiber master batch at 105 ℃ for 22h, and then adding the dried master batch into a spinning machine, wherein the spinning temperature is 220 ℃, and the winding speed is 1500 m/min; the drafting temperature is set to be 100 ℃, and the drafting multiple is 3.7 times, so that the low-melting-point copolyester polylactic acid fiber is finally obtained.
The successful synthesis of the obtained copolymerized master batch can be known through nuclear magnetism and infrared spectra. The low melting point copolyester polylactic acid fiber monofilament has the linear density of 2.0dtex, the breaking strength of 3.8cN/dtex and the elongation at break of 28 percent. The fiber has an obvious melting peak near 170 ℃ measured by Differential Scanning Calorimetry (DSC), and the surface appearance of the fiber is smooth measured under a scanning electron microscope.
Example 4:
and (2) putting 85 parts of L-lactic acid with the purity of 96% weighed according to the parts by weight into a three-neck flask, keeping the vacuum degree of the flask at 1000Pa, adding magnetic stirring, keeping the reaction starting temperature at 95 ℃, keeping the heating rate of 11 ℃/h, heating to 168 ℃, adding 0.12 part of stannous octoate and toluene mixed solution weighed according to the parts by weight as a catalyst at the temperature of 100 ℃, keeping the whole reaction process for 20 hours, and finally obtaining the lactic acid oligomer. Then adding 25 parts of PCL-OH weighed according to parts by weight into the lactic acid oligomer, keeping the vacuum degree of 1000Pa, stirring by magnetic force, and reacting at 175 ℃ for 6.5h to obtain the PLA-PCL copolymer prepolymer. Adding the obtained PLA-PCL copolymer prepolymer into a Haake internal mixer, setting the rotating speed at 90rpm, setting the temperature at 170 ℃ and setting the time for 19min, dropwise adding 2.5 parts of a mixture of diisocyanate (HDI) and Butanediol (BDO) or serving as a small molecular chain extender, which is weighed according to parts by weight, in the 19-min internal mixing process of the Haake internal mixer, and finally obtaining copolymerization modified polylactic acid master batches to obtain copolyester fiber master batches;
drying the copolyester fiber master batch at 108 ℃ for 23h, and then adding the copolyester fiber master batch into a spinning machine, wherein the spinning temperature is 210 ℃, and the winding speed is 1450 m/min; the drafting temperature is set to 95 ℃, and the drafting multiple is 4 times, so that the low-melting-point copolyester polylactic acid fiber is finally obtained.
The successful synthesis of the obtained copolymerized master batch can be known through nuclear magnetism and infrared spectra. The low melting point copolyester polylactic acid fiber monofilament has the linear density of 2.1dtex, the breaking strength of 3.7cN/dtex and the elongation at break of 29 percent. The fiber has an obvious melting peak near 168 ℃ measured by Differential Scanning Calorimetry (DSC), and the surface appearance of the fiber is smooth measured under a scanning electron microscope.
Compared with the common polylactic acid fiber, the low-melting-point copolyester polylactic acid fiber prepared by the embodiments 1 to 4 has the advantages that the flexibility is increased, the tensile strength is slightly reduced, and meanwhile, the melting point of polylactic acid is reduced, so that the spinning temperature of the fiber is reduced, the influence of the temperature on the degradation of the polylactic acid is reduced, and the mechanical property of the fiber is improved. And as the polycaprolactone has biodegradability, the fiber also has biodegradability.
The invention firstly carries out polycondensation reaction on L-lactic acid in the presence of a catalyst to prepare lactic acid oligomer, then polycaprolactone diol is added to carry out copolymerization reaction with the oligomer to obtain PLA-PCL block prepolymer, and finally chain extension reaction is carried out in the presence of diisocyanate and butanediol to increase the molecular weight of the copolymer so as to meet the spinning requirement.
And drying the prepared copolymer, adding the dried copolymer into a spinning machine for melt spinning, and performing a post-treatment process to obtain the fiber. As can be seen by comparing pure polylactic acid materials, the melting point of the copolymer is reduced by 10-15 ℃ compared with that of the pure polylactic acid, and the melting point is reduced along with the reduction of the amount of the polylactic acid in the copolymerization component. The copolymer fiber reduces the tensile strength a little and improves the elongation by 4 to 6 times.
The foregoing shows and describes the general principles and features of the present invention, together with the advantages thereof. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims (9)

1. A preparation method of a low-melting-point copolyester polylactic acid fiber is characterized by comprising the following steps:
firstly, preparing copolyester fiber master batches through three steps of lactic acid self-polymerization, lactic acid oligomer and polycaprolactone diol copolymerization and melt chain extension, and then drying the copolyester fiber master batches and carrying out melt spinning to obtain the low-melting-point copolyester polylactic acid fiber.
2. The preparation method of the low melting point copolyester polylactic acid fiber according to claim 1, wherein the copolyester fiber master batch comprises the following component substances in parts by weight:
70-90 parts of L-LA;
10-30 parts of PCL-OH;
0.1-0.2 part of catalyst;
1-3 parts of a micromolecular chain extender;
the purity of the L-LA is 88-98%;
the catalyst is a mixed solution of stannous octoate and toluene.
3. The method for preparing a low melting point copolyester polylactic acid fiber according to claim 2, wherein the small molecule chain extender is a mixture of diisocyanate (HDI) and Butanediol (BDO).
4. The method for preparing low-melting-point copolyester polylactic acid fiber according to claim 1, wherein the conditions of the lactic acid self-polymerization process are as follows: the vacuum degree is 1000Pa, the magnetic stirring is carried out, the reaction starting temperature is 80-100 ℃, the constant temperature is kept to rise to 175 ℃ of 165-plus-material temperature, the temperature rising rate is 8-12 ℃/min, the catalyst is added at 120 ℃ of 100-plus-material temperature, and the whole reaction time is kept for 16-20 h.
5. The method for preparing low-melting-point copolyester polylactic acid fiber according to claim 1, wherein the copolymerization process conditions of the lactic acid oligomer and the polycaprolactone diol are as follows: the vacuum degree is 1000Pa, magnetic stirring is carried out, PCL-OH is added, and the reaction is kept for 5-7h at the temperature of 155-175 ℃.
6. The method for preparing low-melting-point copolyester polylactic acid fiber according to claim 1, wherein the conditions of the melt chain extension process are as follows: the preparation method is carried out in a Haake internal mixer, the rotating speed of a rotor is 60-100rpm, a micromolecular chain extender is dropwise added, the reaction temperature is set to 155-.
7. The method for preparing low melting point copolyester polylactic acid fiber according to claim 1, wherein the conditions of melt spinning are spinning temperature 190-220 ℃, winding speed 1000-1500m/min, hot drawing temperature 85-110 ℃, and drawing multiple 2.5-4.
8. The method for preparing low-melting-point copolyester polylactic acid fiber according to claim 1, wherein the drying temperature of the master batch of the copolyester fiber is 100-110 ℃, and the drying time is 20-24 h.
9. The method for preparing low melting point copolyester polylactic acid fiber according to claim 1, wherein the monofilament linear density of the low melting point copolyester polylactic acid fiber is 2.1-2.4dtex, the breaking strength is 3.4-3.8CN/dtex, and the elongation at break is 28-32%.
CN202010601860.6A 2020-06-29 2020-06-29 Preparation method of low-melting-point copolyester polylactic acid fiber Pending CN111519272A (en)

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112011848A (en) * 2020-08-21 2020-12-01 安徽同光邦飞生物科技有限公司 Preparation method of medical polylactic acid composite material fiber
CN113881022A (en) * 2021-09-06 2022-01-04 东部湾(扬州)生物新材料有限公司 Polycaprolactone polyol modified polylactic acid and preparation method of polylactic acid fiber
CN114318667A (en) * 2021-12-30 2022-04-12 福建恒安卫生材料有限公司 Preparation method of super-soft biodegradable fiber non-woven fabric

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1594392A (en) * 2004-07-15 2005-03-16 合肥工业大学 Method for preparing film poly-L-lactic acid copolymer by inner plasticizing
CN107974729A (en) * 2017-12-11 2018-05-01 杭州曦茂新材料科技有限公司 A kind of high-ductility acid fiber by polylactic and preparation method and application
CN108559088A (en) * 2018-05-03 2018-09-21 同济大学 The preparation method of polylactic acid base thermoplastic elastomer with shape-memory properties

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1594392A (en) * 2004-07-15 2005-03-16 合肥工业大学 Method for preparing film poly-L-lactic acid copolymer by inner plasticizing
CN107974729A (en) * 2017-12-11 2018-05-01 杭州曦茂新材料科技有限公司 A kind of high-ductility acid fiber by polylactic and preparation method and application
CN108559088A (en) * 2018-05-03 2018-09-21 同济大学 The preparation method of polylactic acid base thermoplastic elastomer with shape-memory properties

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112011848A (en) * 2020-08-21 2020-12-01 安徽同光邦飞生物科技有限公司 Preparation method of medical polylactic acid composite material fiber
CN113881022A (en) * 2021-09-06 2022-01-04 东部湾(扬州)生物新材料有限公司 Polycaprolactone polyol modified polylactic acid and preparation method of polylactic acid fiber
CN114318667A (en) * 2021-12-30 2022-04-12 福建恒安卫生材料有限公司 Preparation method of super-soft biodegradable fiber non-woven fabric

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