CN113025014A - Nucleating agent for polylactic acid and application method thereof - Google Patents
Nucleating agent for polylactic acid and application method thereof Download PDFInfo
- Publication number
- CN113025014A CN113025014A CN202011257455.3A CN202011257455A CN113025014A CN 113025014 A CN113025014 A CN 113025014A CN 202011257455 A CN202011257455 A CN 202011257455A CN 113025014 A CN113025014 A CN 113025014A
- Authority
- CN
- China
- Prior art keywords
- polylactic acid
- nucleating agent
- crystallization
- crystallinity
- temperature
- Prior art date
- Legal status (The legal status 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 status listed.)
- Pending
Links
- 229920000747 poly(lactic acid) Polymers 0.000 title claims abstract description 95
- 239000004626 polylactic acid Substances 0.000 title claims abstract description 94
- 239000002667 nucleating agent Substances 0.000 title claims abstract description 43
- 238000000034 method Methods 0.000 title claims abstract description 18
- 238000002425 crystallisation Methods 0.000 claims abstract description 35
- 230000008025 crystallization Effects 0.000 claims abstract description 35
- 238000012545 processing Methods 0.000 claims abstract description 12
- 150000001875 compounds Chemical class 0.000 claims abstract description 10
- 230000008569 process Effects 0.000 claims abstract description 7
- 230000015572 biosynthetic process Effects 0.000 claims abstract description 5
- 238000011065 in-situ storage Methods 0.000 claims abstract description 3
- 238000003786 synthesis reaction Methods 0.000 claims abstract description 3
- 229920005862 polyol Polymers 0.000 claims description 7
- 150000003077 polyols Chemical class 0.000 claims description 7
- 238000002844 melting Methods 0.000 claims description 6
- 230000008018 melting Effects 0.000 claims description 6
- 238000002156 mixing Methods 0.000 claims description 6
- JVTAAEKCZFNVCJ-UWTATZPHSA-N D-lactic acid Chemical compound C[C@@H](O)C(O)=O JVTAAEKCZFNVCJ-UWTATZPHSA-N 0.000 claims description 3
- 238000007334 copolymerization reaction Methods 0.000 claims description 3
- 229940022769 d- lactic acid Drugs 0.000 claims description 3
- 229930182843 D-Lactic acid Natural products 0.000 claims description 2
- 125000002887 hydroxy group Chemical group [H]O* 0.000 claims 1
- 238000000137 annealing Methods 0.000 abstract description 7
- 238000005516 engineering process Methods 0.000 abstract description 3
- 230000001276 controlling effect Effects 0.000 abstract description 2
- 230000001105 regulatory effect Effects 0.000 abstract description 2
- 238000012360 testing method Methods 0.000 description 10
- 238000001746 injection moulding Methods 0.000 description 6
- HEBKCHPVOIAQTA-UHFFFAOYSA-N meso ribitol Natural products OCC(O)C(O)C(O)CO HEBKCHPVOIAQTA-UHFFFAOYSA-N 0.000 description 6
- FBPFZTCFMRRESA-KVTDHHQDSA-N D-Mannitol Chemical compound OC[C@@H](O)[C@@H](O)[C@H](O)[C@H](O)CO FBPFZTCFMRRESA-KVTDHHQDSA-N 0.000 description 5
- 239000013078 crystal Substances 0.000 description 5
- 239000000463 material Substances 0.000 description 5
- 238000012986 modification Methods 0.000 description 4
- 230000004048 modification Effects 0.000 description 4
- 230000006911 nucleation Effects 0.000 description 4
- 238000010899 nucleation Methods 0.000 description 4
- FBPFZTCFMRRESA-JGWLITMVSA-N D-glucitol Chemical compound OC[C@H](O)[C@@H](O)[C@H](O)[C@H](O)CO FBPFZTCFMRRESA-JGWLITMVSA-N 0.000 description 3
- TVXBFESIOXBWNM-UHFFFAOYSA-N Xylitol Natural products OCCC(O)C(O)C(O)CCO TVXBFESIOXBWNM-UHFFFAOYSA-N 0.000 description 3
- 229920000642 polymer Polymers 0.000 description 3
- 239000000811 xylitol Substances 0.000 description 3
- 235000010447 xylitol Nutrition 0.000 description 3
- HEBKCHPVOIAQTA-SCDXWVJYSA-N xylitol Chemical compound OC[C@H](O)[C@@H](O)[C@H](O)CO HEBKCHPVOIAQTA-SCDXWVJYSA-N 0.000 description 3
- 229960002675 xylitol Drugs 0.000 description 3
- HEBKCHPVOIAQTA-NGQZWQHPSA-N D-Arabitol Natural products OC[C@H](O)C(O)[C@H](O)CO HEBKCHPVOIAQTA-NGQZWQHPSA-N 0.000 description 2
- HEBKCHPVOIAQTA-QWWZWVQMSA-N D-arabinitol Chemical compound OC[C@@H](O)C(O)[C@H](O)CO HEBKCHPVOIAQTA-QWWZWVQMSA-N 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000000113 differential scanning calorimetry Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000000835 fiber Substances 0.000 description 2
- 238000011049 filling Methods 0.000 description 2
- 238000009472 formulation Methods 0.000 description 2
- 235000010355 mannitol Nutrition 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000011159 matrix material Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 239000002105 nanoparticle Substances 0.000 description 2
- PXQPEWDEAKTCGB-UHFFFAOYSA-N orotic acid Chemical compound OC(=O)C1=CC(=O)NC(=O)N1 PXQPEWDEAKTCGB-UHFFFAOYSA-N 0.000 description 2
- 229920003023 plastic Polymers 0.000 description 2
- 239000004033 plastic Substances 0.000 description 2
- 238000011946 reduction process Methods 0.000 description 2
- SERLAGPUMNYUCK-DCUALPFSSA-N 1-O-alpha-D-glucopyranosyl-D-mannitol Chemical compound OC[C@@H](O)[C@@H](O)[C@H](O)[C@H](O)CO[C@H]1O[C@H](CO)[C@@H](O)[C@H](O)[C@H]1O SERLAGPUMNYUCK-DCUALPFSSA-N 0.000 description 1
- 240000008564 Boehmeria nivea Species 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 229920000858 Cyclodextrin Polymers 0.000 description 1
- FBPFZTCFMRRESA-FSIIMWSLSA-N D-Glucitol Natural products OC[C@H](O)[C@H](O)[C@@H](O)[C@H](O)CO FBPFZTCFMRRESA-FSIIMWSLSA-N 0.000 description 1
- UNXHWFMMPAWVPI-QWWZWVQMSA-N D-threitol Chemical compound OC[C@@H](O)[C@H](O)CO UNXHWFMMPAWVPI-QWWZWVQMSA-N 0.000 description 1
- UNXHWFMMPAWVPI-UHFFFAOYSA-N Erythritol Natural products OCC(O)C(O)CO UNXHWFMMPAWVPI-UHFFFAOYSA-N 0.000 description 1
- WQZGKKKJIJFFOK-GASJEMHNSA-N Glucose Natural products OC[C@H]1OC(O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-GASJEMHNSA-N 0.000 description 1
- 239000004113 Sepiolite Substances 0.000 description 1
- 229920003232 aliphatic polyester Polymers 0.000 description 1
- 150000001408 amides Chemical class 0.000 description 1
- 150000001413 amino acids Chemical class 0.000 description 1
- WQZGKKKJIJFFOK-VFUOTHLCSA-N beta-D-glucose Chemical compound OC[C@H]1O[C@@H](O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-VFUOTHLCSA-N 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 239000002041 carbon nanotube Substances 0.000 description 1
- 229910021393 carbon nanotube Inorganic materials 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 238000004132 cross linking Methods 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- GUJOJGAPFQRJSV-UHFFFAOYSA-N dialuminum;dioxosilane;oxygen(2-);hydrate Chemical class O.[O-2].[O-2].[O-2].[Al+3].[Al+3].O=[Si]=O.O=[Si]=O.O=[Si]=O.O=[Si]=O GUJOJGAPFQRJSV-UHFFFAOYSA-N 0.000 description 1
- FPAFDBFIGPHWGO-UHFFFAOYSA-N dioxosilane;oxomagnesium;hydrate Chemical compound O.[Mg]=O.[Mg]=O.[Mg]=O.O=[Si]=O.O=[Si]=O.O=[Si]=O.O=[Si]=O FPAFDBFIGPHWGO-UHFFFAOYSA-N 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 229920006351 engineering plastic Polymers 0.000 description 1
- 230000004927 fusion Effects 0.000 description 1
- -1 heptatol Chemical compound 0.000 description 1
- 229940042795 hydrazides for tuberculosis treatment Drugs 0.000 description 1
- 150000002429 hydrazines Chemical class 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000000905 isomalt Substances 0.000 description 1
- 235000010439 isomalt Nutrition 0.000 description 1
- HPIGCVXMBGOWTF-UHFFFAOYSA-N isomaltol Natural products CC(=O)C=1OC=CC=1O HPIGCVXMBGOWTF-UHFFFAOYSA-N 0.000 description 1
- 239000000832 lactitol Substances 0.000 description 1
- 235000010448 lactitol Nutrition 0.000 description 1
- VQHSOMBJVWLPSR-JVCRWLNRSA-N lactitol Chemical compound OC[C@H](O)[C@@H](O)[C@@H]([C@H](O)CO)O[C@@H]1O[C@H](CO)[C@H](O)[C@H](O)[C@H]1O VQHSOMBJVWLPSR-JVCRWLNRSA-N 0.000 description 1
- 229960003451 lactitol Drugs 0.000 description 1
- 239000000845 maltitol Substances 0.000 description 1
- 235000010449 maltitol Nutrition 0.000 description 1
- VQHSOMBJVWLPSR-WUJBLJFYSA-N maltitol Chemical compound OC[C@H](O)[C@@H](O)[C@@H]([C@H](O)CO)O[C@H]1O[C@H](CO)[C@@H](O)[C@H](O)[C@H]1O VQHSOMBJVWLPSR-WUJBLJFYSA-N 0.000 description 1
- 229940035436 maltitol Drugs 0.000 description 1
- 229960001855 mannitol Drugs 0.000 description 1
- 238000010128 melt processing Methods 0.000 description 1
- 238000010309 melting process Methods 0.000 description 1
- 229960005010 orotic acid Drugs 0.000 description 1
- 238000004806 packaging method and process Methods 0.000 description 1
- CMPQUABWPXYYSH-UHFFFAOYSA-N phenyl phosphate Chemical class OP(O)(=O)OC1=CC=CC=C1 CMPQUABWPXYYSH-UHFFFAOYSA-N 0.000 description 1
- 229920001308 poly(aminoacid) Polymers 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000012552 review Methods 0.000 description 1
- HFHDHCJBZVLPGP-UHFFFAOYSA-N schardinger α-dextrin Chemical compound O1C(C(C2O)O)C(CO)OC2OC(C(C2O)O)C(CO)OC2OC(C(C2O)O)C(CO)OC2OC(C(O)C2O)C(CO)OC2OC(C(C2O)O)C(CO)OC2OC2C(O)C(O)C1OC2CO HFHDHCJBZVLPGP-UHFFFAOYSA-N 0.000 description 1
- 229910052624 sepiolite Inorganic materials 0.000 description 1
- 235000019355 sepiolite Nutrition 0.000 description 1
- 229960002920 sorbitol Drugs 0.000 description 1
- 238000010345 tape casting Methods 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
- 239000002023 wood Substances 0.000 description 1
Classifications
-
- 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
- C08K5/00—Use of organic ingredients
- C08K5/04—Oxygen-containing compounds
- C08K5/05—Alcohols; Metal alcoholates
- C08K5/053—Polyhydroxylic alcohols
-
- 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
- C08K5/00—Use of organic ingredients
- C08K5/04—Oxygen-containing compounds
- C08K5/15—Heterocyclic compounds having oxygen in the ring
- C08K5/151—Heterocyclic compounds having oxygen in the ring having one oxygen atom in the ring
- C08K5/1545—Six-membered rings
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2207/00—Properties characterising the ingredient of the composition
- C08L2207/20—Recycled plastic
- C08L2207/24—Recycled plastic recycling of old tyres and caoutchouc and addition of caoutchouc particles
Landscapes
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Compositions Of Macromolecular Compounds (AREA)
- Biological Depolymerization Polymers (AREA)
Abstract
The invention relates to a nucleating agent for polylactic acid and an application method thereof. The nucleating agent is polyhydroxy compound, and is directly melt blended with polylactic acid in the processing process or added in situ in the polylactic acid synthesis process, so that the aim of regulating and controlling the crystallization behavior of the polylactic acid is fulfilled. The nucleating agent can simultaneously improve the crystallization temperature, the crystallinity and the crystallization rate of the polylactic acid. By adopting the conventional processing technology, the polylactic acid product does not need additional annealing treatment, and the heat resistance of the polylactic acid product can be greatly improved. Provides a simple and efficient way for solving the problem of poor heat resistance of the polylactic acid.
Description
Technical Field
The invention belongs to a crystallization behavior of polylactic acid and a heat resistance regulation technology thereof, and particularly relates to a method for promoting crystallization of polylactic acid and improving heat resistance thereof by using a polyhydroxy compound as a nucleating agent of the polylactic acid.
Background
The polylactic acid has the potential of replacing conventional plastics by virtue of good biodegradability, biocompatibility and mechanical properties, but the consumption amount and the application field of the polylactic acid are far inferior to those of general plastics. The reason is that some problems still remain to be solved in polylactic acid: like most aliphatic polyesters, polylactic acid has weak crystallization ability, slow crystallization rate, low crystallinity, and poor adaptability to processing conditions. The film is mainly formed by injection molding, tape casting and other processes, and is not easy to blow film. In addition, the polylactic acid product has high brittleness and low elongation at break, and especially has poor heat resistance (generally the using temperature is not more than 60 ℃), which limits the application of polylactic acid in the field of high heat resistance and becomes a difficult problem which troubles academia and industry for many years. At present, polylactic acid cannot be used in the fields of engineering plastics such as food takeaway lunch boxes, biomedical materials, electric appliances, automotive interiors and the like with heat-resistant requirements. Therefore, it is very important to improve the crystallization property and heat resistance of polylactic acid to widen its application field.
The heat resistance of a crystalline polymer is closely related to its crystallization behavior and crystallinity. At present, the most effective way for improving the heat resistance of polylactic acid is to blend levorotatory polylactic acid (PLLA) and dextrorotatory polylactic acid (PDLA) in an equimolar ratio to form a stereo-complex crystal (SC), wherein the melting point of the SC can reach 220-230 ℃, and the heat resistance is obviously improved. However, when the molecular weight exceeds a certain threshold, the formation of stereocomplex crystals is hindered; and the cost of the poly-D-lactic acid is higher, the relative dosage is large (equal molar ratio), and the traditional melting process is not suitable for the formation of the stereo complex crystal. Subsequently, researchers have attempted to improve the crystallization rate and tensile strength of polylactic acid using stereocomplex crystals as nucleating agents and crosslinking points. However, once the processing temperature exceeds the melting point of the stereocomplex crystal, the stereocomplex structure is destroyed and cannot be recovered [ Polymer Reviews, 2016, 56(2), 262-. It is obvious that the melting point of polylactic acid can be increased by the stereocomplex technique route, but it is difficult to realize industrialization.
There are other methods for improving the heat resistance of polylactic acid, such as copolymerization, blending, nanoparticle or fiber filling, and increasing crystallinity, etc. The components introduced by the modes of copolymerization, blending, filling and the like have high content, so that the degradation of the polylactic acid is influenced, and the application of the polylactic acid in the field with high requirements on biological safety is limited. Further, the Heat Distortion Temperature (HDT) of the article is still 100 ℃ or lower, and there is a case where the mechanical properties are lowered. Therefore, improving the crystallinity of polylactic acid by controlling the crystallization behavior of polylactic acid is the most effective method for solving the heat resistance defect of polylactic acid.
In recent years, much research on the regulation of the crystallization behavior of polylactic acid focuses on a simpler and more efficient method, namely adding a nucleating agent. The inorganic nucleating agent for polylactic acid is mainly nano particle and nano layered material, including talcum powder, sepiolite, modified montmorillonite, carbon nanotube, etc. These nucleating agents have a significant nucleating effect, but generally do not increase in crystallinity.
The organic nucleating agent used for polylactic acid has various molecular structures. The main reports to date are amides, hydrazines and hydrazides, phenylphosphates, branched polylactic acids, amino acids and polyamino acids. In addition, there are also some biobased materials and their derivatives that can be used as nucleating agents for polylactic acid, such as: orotic acid, cyclodextrin, ramie fiber, wood powder, etc.
Although various nucleating agents can improve the crystallization rate and the non-isothermal crystallization rate of the polylactic acid to different degrees, the crystallinity of the polylactic acid is generally not more than 30 percent in the temperature reduction process, the heat distortion temperature can be only improved to 60-70 ℃ from about 55 ℃, and the limited improvement range has little practical significance. In order to further improve the heat resistance of polylactic acid, it is necessary to add a nucleating agent and then to perform annealing treatment, and further improve the crystallinity by the cold crystallization process [ ACS Applied Materials & processes, 2015,7 (21): 11203-14]. It was found that the annealing treatment can raise the heat resistant temperature of the polylactic acid to 120 ℃ or higher [ Journal of Applied Polymer Science,2019,136(8) ], but the annealing treatment not only increases the complexity of the production process but also greatly reduces the production efficiency. At present, the heat resistance of polylactic acid regulated by a nucleating agent is not satisfactory.
Therefore, there is a need to find a nucleating agent which can adapt to the conventional melt processing technology and can significantly improve the heat resistance of polylactic acid without annealing treatment.
Disclosure of Invention
The invention aims to solve the defect of poor heat resistance of polylactic acid in practical use, discloses a polyhydroxy compound as a polylactic acid nucleating agent, can simultaneously improve the crystallization temperature, the crystallinity and the crystallization rate of the polylactic acid, can improve the processability of the polylactic acid, and can greatly improve the heat resistance of the polylactic acid without annealing treatment.
In order to achieve the purpose, the invention is realized by the following technical scheme:
polyhydroxy compound is used as nucleating agent of polylactic acid. The amount of the nucleating agent in the polylactic acid is less than 2.0 percent (mass), and preferably 0.1 to 1.0 percent (mass).
The polyol nucleating agent has a melting point of less than 170 ℃ and comprises: d-sorbitol, D-mannitol, D-glucose, D-arabitol, xylitol, threitol, heptatol, maltitol, isomalt, lactitol, and the like, but is not limited to the above-listed polyols.
The polylactic acid is L-polylactic acid, wherein the content of D-lactic acid is less than 2%.
The application method of the polyhydroxy compound as the nucleating agent of the polylactic acid comprises the following steps:
the application method of the nucleating agent comprises two modes: one is that the dispersion of the nucleating agent in the polylactic acid matrix is realized by melt blending in the polylactic acid processing process; the other is added in situ during the polylactic acid synthesis. The addition of the nucleating agent can simultaneously improve the crystallization temperature, the crystallinity and the crystallization speed of the polylactic acid, obviously shorten the processing period and obviously improve the heat resistance of the polylactic acid under the condition of not annealing treatment.
Through the technical scheme of the invention, the following advantages can be brought:
the invention discloses a novel nucleating agent which takes polyhydroxy compound as the nucleating agent of polylactic acid, can play an excellent nucleating role, thereby effectively improving the heat resistance and the service performance of the polylactic acid.
Compared with inorganic nucleating agents and organic nucleating agents, the nucleating agents are mostly derived from biological base materials, can be safely metabolized in human bodies, have no toxic or side effect on the application of polylactic acid in the fields of heat-resistant food packaging and biomedicine, and have outstanding green and biological safety advantages. From the aspect of processing, the nucleating agent has good compatibility with polylactic acid and is easily and uniformly dispersed in a polylactic acid matrix.
The present invention is further illustrated by the following specific embodiments, which are not meant to limit the scope of the invention.
Detailed Description
The crystallization temperature in the following examples is the temperature of the sample after mixing, and the Differential Scanning Calorimeter (DSC) is used to raise the temperature to eliminate the heat history, and then the crystallization peak temperature (the temperature reduction rate is 10 ℃/min) is measured in the programmed temperature reduction process; the crystallinity is an injection molding product, and is calculated by a DSC direct temperature rise test (the temperature rise rate is 10 ℃/min), and the calculation formula (1) is as follows:
wherein, Δ HmIs the enthalpy of fusion; Δ HccThe enthalpy of heat release when cold crystallization occurs;
is the standard melting enthalpy of polylactic acid, 93.7J/g;
is the mass fraction of the nucleating agent.
Example 1
The formula is as follows: d-sorbitol, 0.7% (mass), the balance polylactic acid.
Processing conditions are as follows: polyhydroxy compound (D-sorbitol) and polylactic acid in the formula are mixed for 8 minutes at the temperature of 190 ℃, then a sample is obtained by injection molding, and a differential scanning calorimeter and a heat distortion temperature tester are adopted to respectively test the crystallinity and the heat distortion temperature.
And (3) testing results: the crystallization temperature of the polylactic acid is increased from 94 ℃ when the polylactic acid is not modified to 110 ℃, and the crystallization rate is increased. The crystallinity of the sample is improved from 19 percent when the sample is not modified to 55 percent after nucleation modification; the heat distortion temperature increased from 58 ℃ when unmodified to 135 ℃.
Example 2
The formula is as follows: d-mannitol in an amount of 0.5% by mass, with the balance polylactic acid.
Processing conditions are as follows: the polyhydroxy compound (D-mannitol) in the formula and polylactic acid are mixed for 8 minutes at the temperature of 190 ℃, then a sample is obtained by injection molding, and a differential scanning calorimeter and a heat distortion temperature tester are adopted to respectively test the crystallinity and the heat distortion temperature.
And (3) testing results: the crystallization temperature of polylactic acid is increased from 94 ℃ when unmodified to 107 ℃, and the crystallization rate is increased. The crystallinity of the sample is improved from 19 percent when the sample is not modified to 46 percent after nucleation modification; the heat distortion temperature was increased from 58 ℃ when unmodified to 115 ℃.
Example 3
The formula is as follows: xylitol, 2% (mass), the balance polylactic acid.
Processing conditions are as follows: the polyol (xylitol) in the formulation was kneaded with polylactic acid at a temperature of 190 ℃ for 8 minutes, followed by injection molding to obtain a sample. And respectively testing the crystallinity and the thermal deformation temperature by adopting a differential scanning calorimetry calorimeter and a thermal deformation temperature tester.
And (3) testing results: the crystallization temperature of polylactic acid is increased from 94 ℃ when unmodified to 112 ℃, and the crystallization rate is increased. The crystallinity of the sample increased from 19% when unmodified to 53% after nucleation modification; the heat distortion temperature is increased from 58 ℃ when unmodified to 130 ℃.
Example 4
The formula is as follows: d-arabitol in an amount of 0.7 percent by mass, and the balance polylactic acid.
Processing conditions are as follows: the polyol (D-arabitol) in the formulation was kneaded with polylactic acid at a temperature of 190 ℃ for 8 minutes, followed by injection molding to obtain a sample. And respectively testing the crystallinity and the thermal deformation temperature by adopting a differential scanning calorimetry calorimeter and a thermal deformation temperature tester.
And (3) testing results: the crystallization temperature of polylactic acid is increased from 94 ℃ when unmodified to 109 ℃, and the crystallization rate is increased. The crystallinity of the sample is improved from 19 percent when the sample is not modified to 48 percent after nucleation modification; the heat distortion temperature increased from 58 ℃ when unmodified to 105 ℃.
In examples 1-4, the results of non-isothermal tests on polylactic acid with the nucleating agent added show that the crystallization temperature, the crystallinity and the crystallization rate are all significantly improved, the crystallization period is obviously reduced, and the heat resistance of the polylactic acid is greatly improved.
Claims (6)
1. The nucleating agent can simultaneously improve the crystallization temperature, the crystallinity and the crystallization rate of the polylactic acid, and is characterized in that: the polylactic acid is levorotatory polylactic acid (PLLA); the nucleating agent is polyhydroxy compound; the nucleating agent is added into the polylactic acid by means of blending or copolymerization.
2. Polylactic acid according to claim 1, characterized in that: the content of D-lactic acid in the L-polylactic acid is less than 2 percent.
3. The nucleating agent for polylactic acid according to claim 1, characterized in that: the polyhydroxy compounds in the present invention contain more than three hydroxyl groups per molecule and do not exclude other groups in the molecule.
4. The nucleating agent for polylactic acid according to claim 1, characterized in that: the melting point of the polyol nucleating agent is lower than 170 ℃; the polyol is exemplified by, but not limited to, those listed in Table 1.
TABLE 1 examples of polyols
5. The nucleating agent for polylactic acid according to claim 1, characterized in that: the amount of the nucleating agent in the polylactic acid is less than 2.0 percent (mass), and preferably 0.1 to 1.0 percent (mass).
6. The method for applying polylactic acid nucleating agent according to claim 1, wherein: the application forms of the nucleating agent comprise two forms, namely, the nucleating agent and the polylactic acid are mixed by melt blending in the polylactic acid processing process; the other is added in situ during the synthesis of polylactic acid.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011257455.3A CN113025014A (en) | 2020-11-13 | 2020-11-13 | Nucleating agent for polylactic acid and application method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011257455.3A CN113025014A (en) | 2020-11-13 | 2020-11-13 | Nucleating agent for polylactic acid and application method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113025014A true CN113025014A (en) | 2021-06-25 |
Family
ID=76458999
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011257455.3A Pending CN113025014A (en) | 2020-11-13 | 2020-11-13 | Nucleating agent for polylactic acid and application method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113025014A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113667102A (en) * | 2021-08-20 | 2021-11-19 | 浙江大学衢州研究院 | Method for preparing high-molecular-weight polylactic acid based on nucleating agent |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4016118A (en) * | 1974-08-16 | 1977-04-05 | E. C. Chemical Industries & Co., Ltd. | Polyolefin plastic compositions |
| WO2008010318A1 (en) * | 2006-07-18 | 2008-01-24 | Unitika Ltd. | Biodegradable resin composition, method for producing the same, and molded body using the same |
| WO2008099586A1 (en) * | 2007-02-15 | 2008-08-21 | Tokyo Institute Of Technology | Biodegradable resin composition |
| CN102086299A (en) * | 2011-01-14 | 2011-06-08 | 中国科学院宁波材料技术与工程研究所 | Transparent crystallization polylactic acid plastic and preparation method thereof |
| US20140171559A1 (en) * | 2012-12-14 | 2014-06-19 | Dai-Ichi Kogyo Seiyaku Co., Ltd. | Polylactic acid resin composition and resin molded article thereof |
| CN110330476A (en) * | 2019-05-21 | 2019-10-15 | 天津大学 | The glucose hydrazide derivatives and Preparation method and use that acetal replaces |
-
2020
- 2020-11-13 CN CN202011257455.3A patent/CN113025014A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4016118A (en) * | 1974-08-16 | 1977-04-05 | E. C. Chemical Industries & Co., Ltd. | Polyolefin plastic compositions |
| US4016118B1 (en) * | 1974-08-16 | 1988-07-05 | ||
| WO2008010318A1 (en) * | 2006-07-18 | 2008-01-24 | Unitika Ltd. | Biodegradable resin composition, method for producing the same, and molded body using the same |
| WO2008099586A1 (en) * | 2007-02-15 | 2008-08-21 | Tokyo Institute Of Technology | Biodegradable resin composition |
| CN102086299A (en) * | 2011-01-14 | 2011-06-08 | 中国科学院宁波材料技术与工程研究所 | Transparent crystallization polylactic acid plastic and preparation method thereof |
| US20140171559A1 (en) * | 2012-12-14 | 2014-06-19 | Dai-Ichi Kogyo Seiyaku Co., Ltd. | Polylactic acid resin composition and resin molded article thereof |
| CN110330476A (en) * | 2019-05-21 | 2019-10-15 | 天津大学 | The glucose hydrazide derivatives and Preparation method and use that acetal replaces |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113667102A (en) * | 2021-08-20 | 2021-11-19 | 浙江大学衢州研究院 | Method for preparing high-molecular-weight polylactic acid based on nucleating agent |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Arias et al. | Enhanced dispersion of cellulose nanocrystals in melt-processed polylactide-based nanocomposites | |
| Yao et al. | Modification of poly (lactic acid)/poly (propylene carbonate) blends through melt compounding with maleic anhydride | |
| Sharma et al. | Harnessing the ductility of polylactic acid/halloysite nanocomposites by synergistic effects of impact modifier and plasticiser | |
| Jiang et al. | Structure and improved properties of PPC/PBAT blends via controlling phase morphology based on melt viscosity | |
| Zhu et al. | Selective dispersion of carbon nanotubes and nanoclay in biodegradable poly (ε-caprolactone)/poly (lactic acid) blends with improved toughness, strength and thermal stability | |
| JP5285834B2 (en) | Method for producing polylactic acid | |
| Chen et al. | Poly (lactic acid)/poly (butylene succinate)/calcium sulfate whiskers biodegradable blends prepared by vane extruder: Analysis of mechanical properties, morphology, and crystallization behavior | |
| Srithep et al. | Injection molding and characterization of polylactide stereocomplex | |
| Liu et al. | Preparation and characterization of reinforced starch-based composites with compatibilizer by simple extrusion | |
| KR20160026843A (en) | A polylactic acid stereocomplex composition, its molded product, a process for its manufacture and its application | |
| CN109354842B (en) | Polylactic acid composite material and preparation method thereof | |
| CN115232456B (en) | Polyhydroxyalkanoate composition containing hydroxy acid nucleating agent, polyhydroxyalkanoate molded body and preparation method thereof | |
| Santos et al. | Sunflower-oil biodiesel-oligoesters/polylactide blends: Plasticizing effect and ageing | |
| Boruvka et al. | Solid and microcellular polylactide nucleated with PLA stereocomplex and cellulose nanocrystals | |
| Zhu et al. | Enhanced mechanical properties of biodegradable poly (ε-caprolactone)/cellulose acetate butyrate nanocomposites filled with organoclay | |
| JP4894756B2 (en) | Thermoplastic resin composition | |
| Kong et al. | Production and characterization of sustainable poly (lactic acid)/functionalized-eggshell composites plasticized by epoxidized soybean oil | |
| CN113025014A (en) | Nucleating agent for polylactic acid and application method thereof | |
| Gasmi et al. | Crystallization and dielectric behavior of PLA and PHBV in PLA/PHBV blends and PLA/PHBV/TIO 2 nanocomposites | |
| CN115044180A (en) | Polyhydroxyalkanoate composition containing crystallization promoter and molded body | |
| Hou et al. | Novel environmentally sustainable xylitol-based plasticizer: synthesis and application | |
| JP3945264B2 (en) | Polylactic acid composite material and molded body | |
| Yazdaninia et al. | An assessment on the effect of trifluoropropyl-POSS and blend composition on morphological, thermal and thermomechanical properties of PLA/TPU | |
| Li et al. | Thermal and mechanical properties of stereocomplex polylactide enhanced by nanosilica | |
| de la Rosa-Ramírez et al. | Pentaerythritol and glycerol esters derived from gum rosin as bio-based additives for the improvement of processability and thermal stability of polylactic acid |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20210625 |