阅读说明：本技术 一种表面接枝有液体橡胶的氧化锌的制备方法 (Preparation method of zinc oxide with surface grafted with liquid rubber ) 是由 沈显荣 相益信 宋庆平 查冬旺 蒲斌 胡庆松 耿雅婷 于 2019-08-07 设计创作，主要内容包括：本发明涉及一种表面接枝有液体橡胶的氧化锌的制备方法,将氧化锌粒子分散在溶剂中,然后加入带有双键的偶联剂、引发剂、液体橡胶,在一定温度下反应,反应结束后用溶剂洗涤、干燥,制得表面接枝有液体橡胶的氧化锌。本发明为一步反应,操作简单,反应条件温和,便于大规模的生产；本发明的表面接枝有液体橡胶的氧化锌与混炼胶的相容性明显改性,为更有效的发挥橡胶配方中不同组分的协同性能提供较好的基础。(The invention relates to a preparation method of zinc oxide with liquid rubber grafted on the surface, which comprises the steps of dispersing zinc oxide particles in a solvent, adding a coupling agent with double bonds, an initiator and the liquid rubber, reacting at a certain temperature, washing with the solvent after the reaction is finished, and drying to obtain the zinc oxide with the liquid rubber grafted on the surface. The method is a one-step reaction, is simple to operate, has mild reaction conditions, and is convenient for large-scale production; the compatibility of the zinc oxide with the surface grafted with the liquid rubber and the rubber compound is obviously modified, and a better basis is provided for more effectively exerting the synergistic performance of different components in the rubber formula.)

1. A preparation method of zinc oxide with liquid rubber grafted on the surface is characterized by comprising the following steps: dispersing zinc oxide particles in a solvent, adding a coupling agent with double bonds, an initiator and liquid rubber, reacting at a certain temperature, washing with the solvent after the reaction is finished, and drying to obtain the zinc oxide with the surface grafted with the liquid rubber.

2. The method for preparing zinc oxide surface-grafted with liquid rubber according to claim 1, wherein: the zinc oxide is micron-sized zinc oxide or nano-sized zinc oxide.

3. the method for preparing zinc oxide surface-grafted with liquid rubber according to claim 1, wherein: the solvent is any one of dichloromethane, toluene, 1,4 dioxane, tetrahydrofuran, N dimethylformamide and water.

4. The method for preparing zinc oxide surface-grafted with liquid rubber according to claim 1, wherein: the coupling agent with double bonds is maleic anhydride or methacrylic anhydride.

5. The method for preparing zinc oxide surface-grafted with liquid rubber according to claim 1, wherein: the initiator is any one of azobisisobutyronitrile, 1' -azo (cyanocyclohexane), dimethyl azobisisobutyrate, benzoyl peroxide and di-tert-butyl peroxide.

6. The method for preparing zinc oxide surface-grafted with liquid rubber according to claim 1, wherein: the liquid rubber is any one of liquid natural rubber, liquid butadiene rubber, liquid styrene butadiene rubber and liquid nitrile butadiene rubber.

7. The method for preparing zinc oxide surface-grafted with liquid rubber according to claim 1, wherein: the mass ratio of the zinc oxide particles, the liquid rubber, the coupling agent with double bonds, the initiator to the solvent is 1: 0.1-1: 0.01-0.2: 0.005-0.1: 1 to 10.

8. The method for preparing zinc oxide surface-grafted with liquid rubber according to claim 1, wherein: the reaction temperature is 40-150 ℃, and the reaction time is 5-40 h.

9. The method for preparing zinc oxide with liquid rubber grafted on the surface according to claim 1, wherein: and after the reaction is finished, washing the reaction product for three to five times by using dichloromethane, and drying the reaction product for 5 to 36 hours in a vacuum oven at the temperature of 40 to 100 ℃.

10. The method for preparing zinc oxide with liquid rubber grafted on the surface according to claim 1, wherein: the grafted liquid rubber accounts for 0.1-20% of the weight of the zinc oxide particles.

Technical Field

The invention belongs to the technical field of rubber, and particularly relates to a preparation method of zinc oxide with liquid rubber grafted on the surface.

Background

Zinc oxide (ZnO) and stearic acid are commonly used as the active systems in the vulcanization system of rubber materials. The production and use process of zinc oxide can have great influence on the environment. On the premise of improving the performance of rubber materials, the trend of the development of the rubber industry at present is to reduce the consumption of zinc oxide. The particle size, shape, specific surface area and degree of agglomeration of the zinc oxide all affect its active properties. The zinc oxide has extremely large specific surface area and higher specific surface energy, and is not easy to disperse in an organic medium, which directly influences the actual efficacy of the nano zinc oxide. In order to improve the dispersibility and affinity of inorganic particles in organic media and expand the application range of nano materials, the surface of ZnO needs to be modified.

The ZnO surface modification is reported less, and the modification method can refer to the surface modification method of silicon dioxide. Chinese patent CN101220177 and the like disclose a preparation method of a white carbon black/solution polymerized styrene butadiene rubber nano composite material. The method comprises the steps of fully mixing silicon dioxide and a silane coupling agent, carrying out heat treatment at high temperature for condensation reaction to obtain organically modified nano silicon dioxide powder, adding the organically modified nano silicon dioxide powder into solution polymerized styrene-butadiene rubber liquid, stirring, removing a solvent, and drying to obtain the white carbon black/solution polymerized styrene-butadiene rubber nano composite material. Prucker (Macromolecules,1998,3 (31):592-601) modifies silica by conventional free radical polymerization by grafting a nitrogen-containing free radical initiator onto the silica surface and then initiating free radical polymerization by such modified silica particles with polymer chains grafted onto the silica surface.Huck summarizes in SiO₂Methods for grafting polymer molecular brushes onto the surface of spheres include Atom Transfer Radical Polymerization (ATRP), nitroxide-stabilized radical polymerization, reversible addition-fragmentation chain transfer polymerization (RAFT), activated anionic surface initiated polymerization (LASIP), and the like (Chemical society reviews,2004,33, 14-22). Chinese patent CN 107501486A discloses a preparation method and application of nano-silica with polyisoprene grafted on the surface, in the method, silica reacts with RAFT reagent to initiate RAFT polymerization of isoprene, and the nano-silica with polyisoprene grafted on the surface is obtained after washing and drying.

Taghvaei-Ganjali (Journal of Applied Polymer Science,2011,122,249-256.) uses polyethylene glycol (PEG) and polypropylene glycol (PPG) to respectively modify ZnO and nZnO, and the zinc oxide modified particles have larger improvement on the performance of NR/SBR. Wang (Journal of Applied Polymer Science,2011,119,1144-1155.) modifies nano zinc oxide in situ by siloxane coupling agent and uses the nano zinc oxide to reinforce the ethylene propylene diene monomer, and the heat-conducting property of the material is obviously improved. Abbasian (Polymer Engineering & Science,2016,56,187-195.) grafts Polystyrene (PS) to the surface of nano-zinc oxide by complex polymerization methods such as RAFT polymerization methods, which still remain at experimental level and cannot be mass-produced.

Disclosure of Invention

In order to overcome the defects in the prior art, the invention provides a preparation method of zinc oxide with liquid rubber grafted on the surface. The invention solves the problems that the zinc oxide is easy to agglomerate and disperse unevenly in the rubber compound, and the liquid rubber material is grafted on the surface of the zinc oxide only by a one-step method, so that the dispersibility of the zinc oxide material in the rubber material can be improved by the method; the zinc oxide material after surface grafting is improved in dispersibility in rubber, the vulcanization time of chloroprene rubber is shortened by 5-30%, and the tensile strength is improved by 10-30%.

In order to achieve the purpose, the invention adopts the technical scheme that:

A process for preparing the zinc oxide grafted with liquid rubber on its surface includes such steps as dispersing zinc oxide particles in solvent, adding coupling agent with double bond, trigger and liquid rubber, reaction at a certain temp, washing with solvent, and drying.

The invention grafts the liquid rubber on the nano zinc oxide by a one-step method and through the reaction of the coupling agent under the traditional free radical polymerization condition, has obvious grafting effect and is suitable for large-scale production.

Preferably, the zinc oxide is micron-sized zinc oxide or nano-sized zinc oxide.

Preferably, the solvent is any one of dichloromethane, toluene, 1,4 dioxane, tetrahydrofuran, N dimethylformamide and water.

Preferably, the coupling agent with double bonds is maleic anhydride or methacrylic anhydride.

Preferably, the initiator is any one of azobisisobutyronitrile, 1' -azo (cyanocyclohexane), dimethyl azobisisobutyrate, benzoyl peroxide and di-tert-butyl peroxide.

Preferably, the liquid rubber is any one of liquid natural rubber, liquid butadiene rubber, liquid styrene butadiene rubber and liquid nitrile butadiene rubber.

Preferably, the mass ratio of the zinc oxide particles, the liquid rubber, the coupling agent with double bonds, the initiator and the solvent is 1: 0.1-1: 0.01-0.2: 0.005-0.1: 1 to 10.

Preferably, the reaction temperature is 40-150 ℃, and the reaction time is 5-40 h.

Preferably, after the reaction is finished, washing the reaction product for three to five times by using dichloromethane, and drying the reaction product for 5 to 36 hours in a vacuum oven at the temperature of 40 to 100 ℃.

Preferably, the grafted liquid rubber accounts for 0.1-20% of the weight of the zinc oxide particles.

The surface-modified zinc oxide powder is successfully prepared by a one-step method, and the material has good dispersion stability and good compatibility with a rubber compound matrix material; the zinc oxide powder after surface modification is used as a good vulcanization activator, and the mechanical property of vulcanized rubber can be improved, and the mechanical property of a rubber material can also be improved. The preparation method has the advantages of simplicity, convenience, practicability, easy industrialization and the like, and can be directly combined with the existing production process of the inorganic nanoparticles.

Drawings

FIG. 1 is an infrared spectrum of zinc oxide (ZnO), liquid natural rubber (PIP), zinc oxide-grafted liquid rubber (ZnO-g-PIP) of the present invention;

FIG. 2 is a graph showing the thermogravimetric curves of zinc oxide grafted liquid rubbers according to examples 1 to 3 of the present invention;

FIG. 3 is a graph showing the thermogravimetric curves of zinc oxide grafted liquid rubbers of examples 4 to 6 of the present invention.

Detailed Description

The present invention is further described with reference to the following specific examples, which are not intended to be limiting, but are intended to be exemplary only in light of the teachings of the present invention and are not intended to be limiting.