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Method for preparing polylactic acid radiation grafting copolymer with electron accelerator

An electron accelerator and radiation grafting technology, which is applied in the field of preparation of radiation graft copolymers, can solve the problems of large loss of mechanical properties, large penetration depth, and changes in degradation rate of polylactic acid materials, and achieve good surface hydrophilicity and degradation rate, simplified modification process steps, and strong ray penetration

Active Publication Date: 2014-09-03
SICHUAN INST OF ATOMIC ENERGY
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] There are two main methods of modifying PLA by radiation method, one is to use gamma ray radiation to graft and modify PLA, such as Chinese patent ZL200910059240.8 A method of preparing poly(lactic acid) and polyvinylpyrrolidone (Poly-N-vinylpyrrolidone, PVP) copolymer by 60Co-γ-ray radiation grafting was reported, but 60Co -γ-ray radiation has strong penetrating power and large penetration depth to the material, which is easy to affect the bulk properties of the material and cause a large loss of the mechanical properties of the polylactic acid material; and the change of the grafting rate seriously affects the change of the degradation rate Therefore, it is necessary to precisely control the grafting ratio of the grafted copolymer. It is difficult to obtain a constant grafting ratio under the precise absorbed dose due to 60 Co-γ-ray radiation due to shielding or source attenuation. Dendropolymer brings inconvenience

Method used

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Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0029] Distill the N-vinylpyrrolidone under reduced pressure to remove the polymerization inhibitor, the vacuum degree is -0.095MPa, seal the N-vinylpyrrolidone from which the polymerization inhibitor has been removed, and place it in a desiccator for future use.

[0030] Measure 6ml of N-vinylpyrrolidone from which the polymerization inhibitor was removed, dissolve it in 14ml of methanol, and add 0.056ml of acetic acid to form a solution. Measure 11ml of the acetic acid methanol solution of N-vinylpyrrolidone, pour it into the cell culture bottle, then weigh 0.2004g of polylactic acid and put it into the cell culture bottle, and make it completely soaked in the acetic acid methanol solution of N-vinylpyrrolidone middle. Vacuumize and fill with nitrogen repeatedly for 5 times, and finally seal the tube with nitrogen. The sealed tube sample is sent to the accelerator for irradiation, the velocity flow of the accelerator is 2 mA, and the absorbed dose is 2 kGy.

[0031] Take o...

Embodiment 2

[0034] Distill the N-vinylpyrrolidone under reduced pressure to remove the polymerization inhibitor, the vacuum degree is -0.095MPa, seal the N-vinylpyrrolidone from which the polymerization inhibitor has been removed, and put it in a desiccator for future use.

[0035] Measure 6ml of N-vinylpyrrolidone from which the polymerization inhibitor was removed, dissolve it in 14ml of methanol, and add 0.056ml of acetic acid to form a solution. Measure 11ml of the acetic acid methanol solution of N-vinylpyrrolidone, pour it into the cell culture bottle, then weigh 0.2222g of polylactic acid and put it into the cell culture bottle, and make it completely soaked in the acetic acid methanol solution of N-vinylpyrrolidone middle. Vacuumize and fill with nitrogen repeatedly for 5 times, and finally seal the tube with nitrogen. The sealed tube sample is sent to the accelerator for irradiation, the velocity flow of the accelerator is 2 mA, and the absorbed dose is 4 kGy.

[0036] Take out...

Embodiment 3

[0039] Distill the N-vinylpyrrolidone under reduced pressure to remove the polymerization inhibitor, the vacuum degree is -0.095MPa, seal the N-vinylpyrrolidone from which the polymerization inhibitor has been removed, and place it in a desiccator for future use.

[0040] Measure 6ml of N-vinylpyrrolidone from which the polymerization inhibitor was removed, and dissolve it in 14ml of methanol to form a solution. Measure 11ml of the methanol solution of N-vinylpyrrolidone, pour it into the cell culture bottle, then weigh 0.2084g of polylactic acid and put it into the cell culture bottle, and make it completely immersed in the methanol solution of N-vinylpyrrolidone in acetate . Vacuumize and fill with nitrogen repeatedly for 5 times, and finally seal the tube with nitrogen. The sealed tube sample is sent to the accelerator for irradiation, the velocity flow of the accelerator is 4 mA, and the absorbed dose is 8 kGy.

[0041] Take out the irradiated sample, wash the surface of...

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PUM

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Abstract

The invention discloses a method for preparing polylactic acid radiation-grafted copolymers by using an electron accelerator. Firstly, the hydrophilic vinyl monomer is removed from the polymerization inhibitor, then dissolved in methanol or a composite organic solvent containing methanol, and then the polymer Lactic acid is soaked in methanol solution of hydrophilic vinyl monomer, and electron accelerator is used for radiation grafting under nitrogen or vacuum atmosphere. Finally, the polylactic acid after irradiation grafting is washed with water or ethanol to remove unreacted monomers And homopolymer, obtain polylactic acid graft copolymer after vacuum drying; The present invention adopts electron accelerator to carry out grafting modification to polylactic acid, and electron accelerator can accurately control penetration thickness, strictly control grafting density, has avoided adopting radiation During radiation grafting modification, the rays have strong penetrating power and large penetration depth, which is easy to affect the bulk properties of the material, and it is difficult to obtain a constant grafting rate under accurate absorbed dose. It has the advantages of simple process, convenient operation, safety and environmental protection, etc. features.

Description

technical field [0001] The present invention relates to a method for preparing a radiation graft copolymer, in particular to a method for preparing a modified polylactic acid material by grafting hydrophilic vinyl monomers onto polylactic acid by electron accelerator radiation, which belongs to field of biomedical materials. Background technique [0002] Polylactic acid (PLA) is a degradable polyester material approved by the US Food and Drug Administration (FDA) for human use. It not only has excellent mechanical strength and chemical stability, but also has absorbability and environmental degradability, and its degradation products can participate in the human body's tricarboxylic acid cycle, and finally use CO 2 and H 2 The form of O is excreted from the body and will not cause harm to the human body. It can be used as medical surgical sutures, injection microcapsules, microspheres, implants and scaffold materials. However, due to the existence of a large number of est...

Claims

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Application Information

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Patent Type & Authority Patents(China)
IPC IPC(8): C08F283/02C08F226/10C08F220/28C08F220/56C08F2/54
Inventor 陈浩彭朝荣王静霞
Owner SICHUAN INST OF ATOMIC ENERGY