阅读说明：本技术 一种生物降解型聚乳酸基防锈母粒及其制备方法 (Biodegradable polylactic acid-based antirust master batch and preparation method thereof ) 是由 黄红军 狄秋菊 万红敬 李志广 于 2019-12-18 设计创作，主要内容包括：本发明涉及一种生物降解型聚乳酸基气相防锈母粒及其制备方法,该气相防锈母粒原料包括以下重量份数的组分：45-55份的表面改性聚乳酸、8-12份的聚乙烯、10-15份的3,5二硝基苯甲酸六次甲基亚胺、3-8份的苯骈三氮唑或其衍生物、3-8份的钼酸钠、1-5份的亚硝酸钠、1-5份的噻二唑或其衍生物、4-8份的增塑剂及4-8份的增强剂,将上述原料按照特定的顺序混料并共混造粒,即可得到所述气相防锈母粒。本发明制备的气相防锈母粒具有良好的可生物降解性。(The invention relates to a biodegradable polylactic acid-based gas-phase antirust master batch and a preparation method thereof, wherein the gas-phase antirust master batch comprises the following components in parts by weight: 45-55 parts of surface modified polylactic acid, 8-12 parts of polyethylene, 10-15 parts of 3, 5-dinitrobenzoic acid hexamethylene imine, 3-8 parts of benzotriazole or a derivative thereof, 3-8 parts of sodium molybdate, 1-5 parts of sodium nitrite, 1-5 parts of thiadiazole or a derivative thereof, 4-8 parts of plasticizer and 4-8 parts of reinforcing agent, and the raw materials are mixed and blended and granulated according to a specific sequence to obtain the gas-phase antirust master batch. The gas-phase antirust master batch prepared by the invention has good biodegradability.)

1. The biodegradable polylactic acid-based gas-phase antirust master batch is characterized by comprising the following raw materials, by weight, 45-55 parts of surface modified polylactic acid, 8-12 parts of polyethylene, 10-15 parts of 3, 5-dinitrobenzoic acid hexamethylene imine, 3-8 parts of benzotriazole or a derivative thereof, 3-8 parts of sodium molybdate, 1-5 parts of sodium nitrite, 1-5 parts of thiadiazole or a derivative thereof, 4-8 parts of a plasticizer and 4-8 parts of a reinforcing agent.

2. The biodegradable polylactic acid-based gas-phase antirust master batch according to claim 1, wherein the surface-modified polylactic acid is prepared from polylactic acid, a coupling agent and a lubricant in a mass ratio of 1:0.015-0.03: 0.015-0.03.

3. The biodegradable polylactic acid-based gas-phase antirust master batch according to claim 2, wherein the preparation method of the surface-modified polylactic acid comprises the following steps: and crushing the polylactic acid until the mesh number is less than 300 meshes, adding the coupling agent and the lubricant under stirring, and stirring and reacting for 15-30min to obtain the polylactic acid.

4. The biodegradable polylactic acid-based gas phase rust inhibitive masterbatch according to claim 2 or 3,

the coupling agent is selected from one or the combination of more than two of silane coupling agent, titanate coupling agent and aluminate coupling agent;

the lubricant is one or the combination of more than two of zinc stearate, calcium stearate and magnesium stearate.

5. The method for preparing the biodegradable polylactic acid-based gas-phase rust-proof masterbatch according to any one of claims 1 to 4, comprising the steps of:

(1) mixing the surface modified polylactic acid, 3,5 dinitrobenzoic acid hexamethylene imine, benzotriazole or derivatives thereof, sodium molybdate, sodium nitrite and thiadiazole or derivatives thereof, and uniformly stirring to obtain a mixed material 1;

(2) adding the plasticizer, the reinforcing agent and polyethylene into the mixed material 1, and uniformly stirring to obtain a mixed material 2;

(3) and blending and granulating the mixed material 2 to obtain the biodegradable polylactic acid-based gas-phase antirust master batch.

6. The method for preparing the biodegradable polylactic acid-based gas-phase antirust masterbatch according to claim 5, wherein the biodegradable polylactic acid-based gas-phase antirust masterbatch is prepared by the following steps: the stirring temperature in the step (2) was 80 ℃.

Technical Field

The invention relates to a composition of biodegradable polylactic acid-based gas-phase antirust master batch and a preparation method thereof, belonging to the technical field of metal antirust.

Background

With the increasing global population and the increasing shortage of resources, the development of a resource-saving and environment-harmonized society has become a development direction. Statistically, the amount of plastic used globally in 2016 will reach 5 hundred million tons, and global plastic consumption is expected to increase at a rate of 8% per year, with annual consumption of plastic reaching more than 7 hundred million tons per 2030, and plastic waste amounts of approximately 2.6-3 million tons per year.

Plastic packages have become one of the major packaging materials in the consumer goods field, and the application range has been gradually expanded to various mass production fields and transport packaging fields. In the transportation and storage processes of the equipment such as automobiles, steel, machinery, electronics and the like and the inlet and outlet of a production line, gas-phase rust-proof plastic products such as a gas-phase rust-proof film, a gas-phase rust-proof bubble pad and the like are needed to be paved in a container or directly wrapped on a packaged object, so that the situation that oxygen and water react with metal to generate corrosion is prevented. These plastic products have a short service life, typically only one to several months, and become quickly waste after the goods arrive at their destination. The gas-phase rust-proof plastic product is produced by using petroleum as a basic raw material, adding a gas-phase corrosion inhibitor which has volatility and certain vapor pressure like camphor balls and applying a chemical synthesis method. Because of the volatility of the vapor phase corrosion inhibitor, the vapor phase rust-proof material is an environment-friendly material in literature, but the corrosion inhibitor contained in the material cannot be completely volatilized, and the plastic carrier can be naturally rotted after being buried in nature for at least 200 years and is difficult to degrade, so that the energy is consumed and the environment is polluted, therefore, the vapor phase rust-proof plastic product with short service life needs to be produced into a degradable product.

Disclosure of Invention

The invention aims to solve the technical problems and provides a biodegradable polylactic acid-based gas-phase antirust master batch and a preparation method thereof, so that a gas-phase antirust plastic product can be biodegraded, and the problems of environment and energy are solved.

The technical scheme adopted for solving the technical problem of the invention is as follows:

the biodegradable polylactic acid-based gas-phase antirust master batch comprises the following components in parts by weight: 45-55 parts of surface modified polylactic acid, 8-12 parts of polyethylene, 10-15 parts of 3, 5-dinitrobenzoic acid hexamethylene imine, 3-8 parts of benzotriazole or a derivative thereof, 3-8 parts of sodium molybdate, 1-5 parts of sodium nitrite, 1-5 parts of thiadiazole or a derivative thereof, 4-8 parts of plasticizer and 4-8 parts of reinforcing agent.

Specifically, the surface modified polylactic acid is used as a carrier, and a film forming substance replaces the non-degradable resin in the conventional plastic film, so that the product has better natural degradation performance. However, the molecular chain of polylactic acid contains a large amount of COO-bonds with strong polarity, which can cause too strong rigidity of the molecular chain and poor flexibility of the material, and can cause poor fusion of the components in the system, and finally influence the uniformity of the material and the function of the antirust components, so the polylactic acid needs to be subjected to surface modification to reduce the surface polarity and increase the compatibility with other components.

The 3,5 dinitrobenzoic acid hexamethylene imine, benzotriazole or derivatives thereof, sodium molybdate, sodium nitrite, thiadiazole or derivatives thereof and other 5 substances are rust-proof components, 4 synergistic effects are achieved among the 5 components, and the components are as follows: volatilization rate synergy, chemical reaction synergy, molecular spatial structure synergy, adsorption type synergy. The volatilization rate synergy and the adsorption type synergy mean that 5 components have different volatilization rates, the benzotriazole or the derivative thereof with higher vapor pressure and higher volatilization rate volatilizes to the metal surface firstly, quickly occupies the metal surface, is combined with the site in a physical adsorption mode, then the 3, 5-dinitrobenzoic acid hexamethylene imine and the thiadiazole or the derivative thereof volatilize to the metal surface, and then the previous benzotriazole or the derivative thereof is replaced in a chemical adsorption mode to form a more stable complex protective layer. The molecular space structure synergy means that the molecular volumes of 3,5 dinitrobenzoic acid hexamethylene imine and thiadiazole or derivatives thereof are greatly different, and relatively complete coverage can be formed on the metal surface. The chemical reaction synergy means that trace moisture and trace hydrogen ions in the space react with sodium molybdate and sodium nitrite to release strong oxidizing groups, and trace metal atoms are oxidized into metal ions, so that the combination of 3,5 dinitrobenzoic acid hexamethylene imine and thiadiazole or derivatives thereof is facilitated.

Further, the surface modified polylactic acid is prepared from polylactic acid, a coupling agent and a lubricant in a mass ratio of 1:0.015-0.03: 0.015-0.03. The specific method comprises the following steps: drying polylactic acid, crushing to below 300 meshes, adding the coupling agent and the lubricant under stirring, and reacting for 15-30min to obtain the polylactic acid.

In some embodiments of the present invention, the coupling agent is one or a combination of two or more selected from the group consisting of a silane coupling agent, a titanate coupling agent, and an aluminate coupling agent. Preferably, the coupling agent is a silane coupling agent KH 570.

In some embodiments of the invention, the lubricant is one or a combination of two or more of zinc stearate, calcium stearate, and magnesium stearate. Preferably, the lubricant is zinc stearate.

The invention also provides a method for preparing the biodegradable polylactic acid-based gas-phase antirust master batch, which comprises the following steps:

(1) mixing the surface modified polylactic acid, 3, 5-dinitrobenzoic acid hexamethylene imine, benzotriazole or derivatives thereof, sodium molybdate, sodium nitrite and thiadiazole or derivatives thereof, and stirring for 15min to obtain a mixed material 1;

(2) adding the plasticizer, the reinforcing agent and polyethylene into the mixed material 1, and stirring for 30min to obtain a mixed material 2;

(3) and blending and granulating the mixed material 2 to obtain the biodegradable polylactic acid-based gas-phase antirust master batch.

Further, the stirring temperature in the step (2) is 80 ℃.

The biodegradable polylactic acid-based gas-phase antirust master batch prepared by the invention takes biodegradable modified polylactic acid as a carrier material and takes components screened and compounded from national food additive catalogues as antirust core components, and has good biodegradability.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. The implementation conditions used in the examples can be further adjusted according to specific requirements, and the implementation conditions not indicated are generally the conditions in routine experiments.