Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Preparation method of reinforced and toughened polylactic acid

A technology of strengthening and toughening polylactic acid, which is applied in the processing field of polymer materials, can solve the problems of strength reduction, toughness reduction, strength and rigidity reduction, etc., and achieve the effect of weakening the strength difference, increasing the crystallization speed, and benefiting the toughness

Active Publication Date: 2016-04-13
SICHUAN UNIV
View PDF5 Cites 18 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

HuanXu[XuH, ZhongGJ, FuQ.J.ACSApplMaterInterfaces.2012,4(12):6774-6784.] et al prepared polylactic acid and polylactic acid / polyethylene glycol composite materials containing string crystal structure by dynamic pressure-holding injection molding technology , although the strength of the prepared polylactic acid material has increased, but the toughness has decreased; while the toughness of the polylactic acid / polyethylene glycol composite material has increased, but the strength has decreased significantly
[0009] To sum up, the existing methods of toughening polylactic acid are accompanied by the decrease of strength and rigidity, or the process regulation is complicated, or the addition of the second component is difficult to achieve the transparency of polylactic acid materials in the fields of food packaging and biomedicine. and safety and other performance requirements

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Preparation method of reinforced and toughened polylactic acid
  • Preparation method of reinforced and toughened polylactic acid
  • Preparation method of reinforced and toughened polylactic acid

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0033] (1) Polylactic acid (PLA2003D, Natureworks, USA) was selected as the experimental material, its melting index was 6g / 10min (210°C, 2.16Kg), and its weight average molecular weight was 1.85×10 5 g / cm 3 , the molecular weight distribution is 1.73. Dry in a vacuum oven at 60°C for 12 hours under vacuum.

[0034] (2) Put the dried pellets into a multi-stage stretching device consisting of an extruder (1), a confluence (2), a force assembly unit (3), and a cooling roller (4) (see figure 1 ) in the extruder. After the division-deformation-stacking action of the force assembly unit, it flows out from the discharge port, and after being cooled by the cooling roller, the polylactic acid material with a width and thickness of 30mm and 1.5mm respectively is obtained.

[0035] Here, the structure of the multistage stretching device will be described first. figure 1 In the process, the discharge port of the extruder is connected to the feed port of the confluence, and the discha...

Embodiment 2

[0038] (1) Polylactic acid (PLA2003D, Natureworks, USA) was selected as the experimental material, its melting index was 6g / 10min (210°C, 2.16Kg), and its weight average molecular weight was 1.85×10 5 g / cm 3 , the molecular weight distribution is 1.73. Dry in a vacuum oven at 60°C for 12 hours under vacuum.

[0039] (2) Put the dried pellets into a multi-stage stretching device consisting of a single-screw extruder (1), a confluence (2), a force assembly unit (3), and a cooling roll (4) (see figure 1 ) in a single-screw extruder. After the division-deformation-stacking action of the force assembly unit, it flows out from the discharge port, and after being cooled by the cooling roller, the polylactic acid material with a width and thickness of 30mm and 1.5mm respectively is obtained. The temperatures of the feeding port, conveying section, melting section, and homogenizing section of single-screw extruder 1 are 125°C, 185°C, 188°C, and 185°C respectively; the temperatures o...

Embodiment 3

[0043] (1) Polylactic acid (PLA2003D, Natureworks, USA) was selected as the experimental material, its melting index was 6g / 10min (210°C, 2.16Kg), and its weight average molecular weight was 1.85×10 5 g / cm 3 , the molecular weight distribution is 1.73. Dry in a vacuum oven at 60°C for 12 hours under vacuum.

[0044] (2) Put the dried pellets into a multi-stage stretching device consisting of a single-screw extruder (1), a confluence (2), a force assembly unit (3), and a cooling roll (4) (see figure 1 ) in a single-screw extruder. After the division-deformation-stacking action of the force assembly unit, it flows out from the discharge port, and after being cooled by the cooling roller, the polylactic acid material with a width and thickness of 30mm and 1.5mm respectively is obtained. The temperatures of the feeding port, conveying section, melting section, and homogenizing section of the single-screw extruder (1) are respectively 125°C, 185°C, 188°C, and 185°C; 185°C.

[...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
Melt fingeraaaaaaaaaa
Strengthaaaaaaaaaa
Storage modulusaaaaaaaaaa
Login to View More

Abstract

The invention discloses a preparation method of reinforced and toughened polylactic acid. The preparation method is characterized in that during the processing process, the crystallized morphology of the polylactic acid is controlled so as to improve the mechanical property of the polylactic acid. Particularly, during the processing process, certain shearing force fields and certain bidirectional drawing force fields are applied on a polylactic acid melt in different directions through the control of the number and the type of force assembling units, when the shearing and drawing action force is large enough, polylactic acid molecules are directionally arranged in the force field direction at first to form shish, then polylactic acid lamellar crystals are arranged in a direction perpendicular to the shish, and at least, an shish-kebab crystallization structure is formed; and the sizes of crystalline grains are small, besides, a large amount of interfaces are introduced in a polylactic acid material, so that the strength and the toughness of the polylactic acid material are remarkably improved. The more the number of the force assembling units with higher melt deformation degrees is, the higher the strength of the bidirectional drawing force field in the direction perpendicular to the extrusion direction is, and the smaller the mechanical strength difference of the prepared polylactic acid product in the extrusion direction and the direction perpendicular to the extrusion direction is. The preparation method has the advantages that the force assembling units are additionally arranged on a traditional extrusion device, the preparation method is simple in operation, can be produced continuously, is convenient to control, stable in quality, and high in production efficiency, has a good industrial and market prospect, can be widely applied to the preparation of a polylactic acid plate, a polylactic acid sheet and a polylactic acid film material, with high strength and toughness.

Description

technical field [0001] The invention relates to a method for preparing reinforced and toughened polylactic acid by an extrusion method, and belongs to the technical field of polymer material processing. Background technique [0002] Petroleum-based polymer materials are widely used in our production and life due to their light weight, high strength, and easy processing and molding. However, general polymer materials are difficult to degrade and consume a lot of petroleum resources. In order to solve the problems of white pollution and energy crisis, many studies are devoted to replacing petroleum-based polymer materials with degradable plastics, among which polylactic acid materials are widely studied. Polylactic acid is a biodegradable polymer prepared by chemical synthesis using renewable plant resources as raw materials. It gets rid of the dependence on petroleum resources and can be completely degraded into CO 2 and H 2 O. With its good biocompatibility, excellent str...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): B29C47/00B29C47/08B29K67/00
CPCB29C48/00B29C48/267B29K2067/046
Inventor 吴宏郭济伟郭少云夏立超李春海
Owner SICHUAN UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com