CN-121991376-A - Organic-inorganic copolymerized high impact resistant elastomer composite material and preparation method thereof

Abstract

The invention discloses a high impact resistant elastomer composite material based on an organic-inorganic copolymerization strategy and a preparation method thereof. The composite material is prepared by an organic-inorganic copolymerization strategy, and comprises metal oxide nano particles with the particle size of 1-10nm and the surface of which is rich in unsaturated metal sites as an inorganic phase and a polymer network containing dynamic covalent bonds as an organic phase, wherein the inorganic phase and the organic phase are connected through chemical bonds to form an organic-inorganic hybridization structural unit with molecular scale, so that the uniform dispersion and the strong interface combination of the inorganic phase are realized. The preparation method comprises the steps of regulating and synthesizing zinc oxide nano particles with unsaturated sites on the surface through a regulator, carrying out pre-coordination assembly on the zinc oxide nano particles and lipoic acid monomers to form lipoic acid-zinc oxide hybrid monomers, and carrying out thermal polymerization to obtain the elastomer composite material. The elongation at break of the obtained material reaches 541 percent, is improved by about 12 times compared with pure poly lipoic acid, can attenuate more than 90 percent of impact force in drop hammer impact test, can bear the impact strain rate of up to 4000s ‑1 , and can realize the self-healing of damage without external force at room temperature. The material has excellent shock resistance, high toughness, intrinsic self-healing capacity and solvent resistance stability, and the preparation method is simple and controllable, and has wide application prospect in the fields of personal protection, aerospace, flexible electronics and the like.

Inventors

• ZHANG WEINA
• HUO FENGWEI
• LI KEXIN
• LI XUERONG
• YAO HONGTAO
• WEI XINPENG

Assignees

• 南京工业大学

Dates

Publication Date

20260508

Application Date

20260306

Claims (10)

1. 1. The high impact resistant elastomer composite material based on the organic-inorganic copolymerization strategy is characterized in that the composite material is a hybrid network material prepared by the organic-inorganic copolymerization strategy, and comprises metal oxide nano particles with the particle size of an inorganic phase of 1-10nm and the surface of the metal oxide nano particles being rich in unsaturated metal sites, wherein the organic phase contains a polymer network with dynamic covalent bonds. Wherein, the inorganic phase and the organic phase are connected through chemical bonds to form an organic-inorganic hybrid structural unit with molecular scale, and the inorganic phase is uniformly dispersed in the organic phase.
2. 2. The composite material according to claim 1, wherein the chemical bond between the inorganic phase and the organic phase is a coordinate bond or a covalent bond, specifically an unsaturated metal site on the surface of the metal oxide nanoparticle is coordinated or reacted with a carboxyl group, a sulfhydryl group or an amino group on a monomer or a polymer chain of the organic phase.
3. 3. Composite material according to claim 1 or 2, characterized in that the inorganic phase is zinc oxide (ZnO), preferably zinc oxide nanoparticles with surface rich in unsaturated zinc sites synthesized by means of regulator regulation.
4. 4. A composite material according to claim 3, wherein the modifier is a low boiling point small organic molecule having a chemical action with metal ions or an organic matrix, preferably triethylamine. .
5. 5. The composite material of claim 1, wherein the organic phase is a poly-lipoic acid (PTA) network formed based on ring-opening polymerization of lipoic acid (TA), and the backbone contains dynamic disulfide bonds.
6. 6. A method of making the high impact elastomer composite of any of claims 1-5, comprising the steps of: Step 1, preparing a zinc oxide precursor, namely dissolving a zinc source in a solvent, adding a regulator under stirring, uniformly mixing, and heating for reaction to obtain zinc oxide suspension rich in unsaturated zinc sites; Step 2, preparing lipoic acid-zinc oxide hybrid monomer, namely dissolving lipoic acid in a solvent, adding the zinc oxide suspension obtained in the step 1 for coordination assembly, and obtaining lipoic acid-zinc oxide hybrid monomer powder through post-treatment; And 3, forming the elastomer composite material, namely filling the hybrid monomer powder obtained in the step 2 into a mould, and heating and polymerizing to obtain the high-impact-resistance elastomer composite material.
7. 7. The method according to claim 6, wherein the zinc source in step 1 is zinc acetate dihydrate, the solvent is methanol, the regulator is triethylamine, the reaction temperature is 50-70 ℃, and the reaction time is 1-3 hours.
8. 8. The method of claim 6, wherein the coordination complex of step 2 is stirred at room temperature for 2-6 hours, and the post-treatment comprises concentration, washing, centrifugation, and freeze-drying.
9. 9. The method according to claim 6, wherein the temperature of the heating polymerization in step 3 is 110 to 160℃and the polymerization time is 0.5 to 2 hours.
10. 10. The method according to claim 6, wherein the mechanical properties and the crosslink density of the resulting composite are controlled by adjusting the molar ratio of lipoic acid to zinc oxide in step 2, or the polymerization temperature in step 3.

Description

Organic-inorganic copolymerized high impact resistant elastomer composite material and preparation method thereof Technical Field The invention relates to the technical field of polymer composite materials, in particular to an elastomer composite material with high impact resistance, high toughness and self-repairing function based on an organic-inorganic copolymerization strategy and a novel preparation method thereof. Background The high-performance impact-resistant material is a core foundation stone for guaranteeing the life safety of personnel under extreme dynamic load and maintaining the structural integrity of equipment in a complex service environment, and has indispensable strategic value in key fields such as personal protection, vehicle armor, aerospace, buffer packaging of precise instruments and the like. Traditional impact-resistant materials such as high-strength steel, aluminum alloy, engineering ceramics and the like mainly depend on high strength to resist deformation, but have inherent limitations such as high density, poor flexibility, incapability of self-recovery after damage and the like. In order to meet the requirements of modern equipment for light weight and flexibility, polymer-based impact resistant materials are attracting attention due to their light weight, high toughness and excellent energy dissipation capability. However, single polymeric materials tend to have insufficient modulus and are prone to irreversible fracture under extreme impact. For this reason, researchers have attempted to introduce metal oxide nanoparticles as a stiffening phase in order to construct composite materials that have both stiffness and toughness. Successful implementation of this strategy has long been limited by a core science challenge-organic-inorganic interfacial incompatibility. Because of the great difference of the chemical properties of the surfaces of the high polymer and the metal oxide, the nano particles are extremely easy to agglomerate in the polymer matrix to form stress concentration points, so that the reinforcing effect is weakened, and the nano particles become crack initiation sources in the impact process, so that the material fails in advance. In order to solve the problem, the existing interface regulation strategies have limitations in terms of interface bonding firmness, structural uniformity or process controllability, and it is difficult to fundamentally realize uniform mixing and firm bonding of organic-inorganic components. The invention provides a high impact resistant elastomer composite material based on an organic-inorganic copolymerization strategy and a preparation method thereof, wherein the growth of metal oxide is controlled by introducing a regulator to obtain a self-healing composite material with small particle size, good dispersibility and close combination with an organic matrix, and the self-healing composite material can keep a stable form under high-speed impact. Disclosure of Invention The invention provides an organic-inorganic copolymerization strategy of a high molecular monomer-metal oxide structural unit. The strategy selects the poly-lipoic acid constructed by dynamic disulfide bonds as an organic matrix, the dynamic network of the poly-lipoic acid has the energy dissipation capacity, and zinc oxide nano particles with the surfaces rich in unsaturated coordination sites are selected as inorganic reinforcing phases. The zinc oxide and the lipoic acid monomer are driven to be pre-coordinated and assembled before polymerization to form a stable hybridized structural unit connected by coordination bonds, so that interface firmness and compounding uniformity are ensured, and then the controllable thermal polymerization is carried out to successfully construct the poly lipoic acid/zinc oxide molecular hybridization network. The test results of mechanical properties and impact resistance show that the material has excellent rigidity-toughness balance and energy dissipation capacity and self-healing property. The method has simple process, good applicability and high controllability, and provides a brand new idea for designing new generation of high-performance dynamic impact resistant materials. The technical scheme adopted for realizing the purpose of the invention is that the high impact resistant elastomer composite material based on an organic-inorganic copolymerization strategy and the preparation method thereof are characterized in that the inorganic phase and the organic phase are connected through chemical coordination bonds or covalent bonds, specifically, unsaturated metal sites on the surfaces of the metal oxide nano particles are coordinated or reacted with carboxyl, sulfhydryl or amino groups on organic phase monomers or polymer chains to form organic-inorganic hybridization structural units with molecular dimensions, thereby realizing uniform dispersion and strong interface combination of the inorganic phase. The preparation method co