Method for accelerating crystallization of polylactic acid resin

A polylactic acid resin and crystallization technology, which is applied in the field of accelerated crystallization of polylactic acid resin, can solve the problems of difficulty in achieving uniform dispersion, affecting the overall performance of products, and large differences in chemical structure, so as to speed up the crystallization speed, improve the nucleation effect, and improve Effect of Machinability and Thermal Properties

Active Publication Date: 2013-11-20
ZHEJIANG UNIV
View PDF1 Cites 9 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Researchers have found that talc, phenyl phosphate, carbon nanotubes, nano-silica and other substances can be used as nucleating agents for polylactic acid, although these inorganic nucleating agents can significantly increase the crystallization rate and crystallinity of polylactic acid, However, the chemical structure of these substances and the polylactic acid matrix is ​​quite different, the compatibility is poor, and it is difficult to achieve uniform dispersion during the mixing process, which may affect the overall performance of the product

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
  • Method for accelerating crystallization of polylactic acid resin

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0019] The preparation method of the semi-crystalline polylactic acid resin is not particularly limited, for example, polylactic acid can be obtained by ring-opening polymerization of L, L-type, D, L-type lactide, L-type, D-type or racemic lactic acid Polylactic acid is obtained by direct polycondensation, and polylactic acid is obtained by three-dimensional crosslinking of polylactic acid by light, heat, radiation, and crosslinking agents. Semi-crystalline polylactic acid resin can also use known inorganic fillers, fillers, and flame retardants. In addition to the above-mentioned components, well-known plasticizers, heat stabilizers, light stabilizers, antioxidants, and anti-hydrolysis agents can also be used together. , internal and external lubricants, impact modifiers, antistatic agents, colorants, release agents, foaming agents, pigments, antibacterial and anti-enzyme agents, coupling agents, other fillers, other nucleating agents, and general synthetic resins Auxiliaries...

Embodiment 1

[0022] Embodiment 1: the preparation of pure polylactic acid spline

[0023] 100 parts of vacuum-dried semi-crystalline poly-L-lactic acid (Shimazu company 9020 grade, containing about 1.5% of D configuration, weight average molecular weight of 186,000) were extruded in a twin-screw extruder at 190 °C, drawn into strands, and Cool in the air and granulate.

[0024] Test of crystallization speed: use DSC test, nitrogen atmosphere. In the non-isothermal DSC test, the sample was heated from room temperature to 190 °C at 100 °C / min, kept for 2 min to eliminate thermal history, cooled to 30 °C at 10 °C / min, kept at 30 °C for 2 min, and then heated at 10 °C / min to 190°C. In the isothermal DSC analysis, the sample was heated from room temperature to 190 °C at 100 °C / min, kept for 2 min to eliminate thermal history, rapidly cooled to 120 °C at 100 °C / min, kept for 60 min, and then raised to 10 °C / min 190°C.

[0025] The crystallinity during cooling at 10 °C / min was calculated fro...

Embodiment 2

[0027] Vacuum-dried semi-crystalline poly-L-lactic acid (Shimazu company's 9020 grade, containing about 1.5% of the D configuration, with a weight average molecular weight of 186,000) 99 parts and PVDF (Wu Yu Chemical Company, KF850 grade) 1 part at 190 °C Extrude in a twin-screw extruder, draw strands, cool in air, and pelletize. The calculated crystallization kinetics and thermal performance parameters are shown in Table 1.

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

No PUM Login to view more

Abstract

The invention relates to the technical field of polylactic acid modification and aims to provide a method for accelerating crystallization of polylactic acid resin. The method comprises the specific steps of: adding a semi-crystalline polylactic acid resin and a polymer-type crystallization promoter into a mixing apparatus; then mixing well in the mixing apparatus; and extruding for granulation, so as to obtain a rapid crystallization modification polylactic acid resin. The method employs organic high-molecular polymer-type crystallization promoter to improve crystallization performance of the polylactic acid, and the promoter has good compatibility with polylactic acid, improves nucleation effect, accelerates crystallization of polylactic acid, and improves processability and thermal behavior of the polylactic acid. Furthermore, a commercialized semi-crystalline polymer polyvinylidene fluoride having similar melting point as polylactic acid is used as the crystallization promoter for polylactic acid, and a melt blending method can be employed. The method provided by the invention has simple process, low cost and can realize large-scale industrialized production.

Description

technical field [0001] The invention relates to the technical field of polylactic acid modification, in particular to a method for accelerating the crystallization of polylactic acid resin. Background technique [0002] With the deteriorating environmental and energy problems such as global warming, "white pollution" of plastic waste, and increasingly scarce fossil resources, bio-based and biodegradable polymer materials have attracted more and more attention. Polylactic acid is a thermoplastic polymer material made from biomass renewable resources. It gets rid of the dependence on petroleum resources, and the environmental load caused by the manufacturing process is small. It has good compostability and biodegradability. The carbon dioxide and water produced by degradation can be returned to nature and rejoined in the photosynthesis process of plants, thus maintaining the balance of the carbon cycle on the earth. Polylactic acid has good mechanical properties, similar to p...

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): C08L67/04C08L27/16B29B9/06
Inventor 潘鹏举单国荣包永忠
Owner ZHEJIANG UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap