CN113683856B - A lightweight and high-strength solid buoyancy material and its preparation method - Google Patents

Abstract

The invention discloses a lightweight and high-strength solid buoyancy material, which includes the following parts by weight of raw materials: 182.06-472.25 parts of a polymer base material system and 50-100 parts of hollow glass beads; the viscosity of the polymer base material system is 100 -500mPa·s, including 100 parts of epoxy vinyl ester resin, 20-100 parts of epoxidized polybutadiene, 20-80 parts of cross-linking agent, 20-100 parts of cross-linking monomer, 15-70 parts of curing agent , 5-20 parts of initiator, 0.05-0.2 parts of accelerator, 0.01-0.05 parts of polymerization inhibitor, 2 parts of surface treatment agent; the particle size of the hollow glass microspheres is 10-150 μm, and the density is 0.10-0.30g/ cm ³ , the compressive strength is 2‑20MPa. This solid buoyancy material has a high filling rate of hollow glass beads, high modulus and excellent machining performance. It is a lightweight and high-strength solid buoyancy material suitable for shallow depths of less than 4,000 meters.

Description

A lightweight and high-strength solid buoyancy material and its preparation method

Technical field

The present invention relates to the field of special materials. More specifically, it relates to a lightweight and high-strength solid buoyancy material and a preparation method thereof.

Background technique

Solid buoyancy materials are the most commonly used materials in ocean survey and ocean engineering, and are also one of the six key technologies for deep submersibles.

The performance requirements of solid buoyancy materials are mainly compressive strength and density. The compressive strength is related to the water depth of the material's application, and the density is related to the buoyancy the material can provide. In applications in shallow seas below 4,000 meters, density is a more critical performance indicator because the ambient water pressure is low. The smaller the density, the greater the buoyancy provided by the solid buoyancy material, which is more conducive to increasing the payload of underwater devices and reducing manufacturing costs. Therefore, effectively reducing the density of solid buoyancy materials for shallow seas has always been the key to its research and development.

In order to reduce the density, some patents use the method of compounding hollow glass beads with organic hollow spheres to obtain low-density solid buoyant materials by adding lighter-density fillers. Qiao Yingjie et al. (CN104448719A) used a compounding method of organic and inorganic hollow microspheres to prepare solid buoyant materials with a density of 0.40-0.45g/ ^cm3 . Zhong Southeast et al. (CN106905662A) used foamed polymer microspheres and hollow glass microspheres as filling materials to prepare a solid buoyancy material with a density of 0.25-0.30g/ ^cm3 .

In addition, increasing the filling rate of hollow balls is also a common method. To achieve this, it is necessary to introduce hollow plastic balls or millimeter-scale composite hollow balls on the basis of adding hollow glass microspheres. For example, Wu Xinfeng et al. (CN104059334A, CN109651765A) added centimeter-sized carbon fiber-reinforced epoxy resin hollow spheres to the system to obtain a solid buoyant material with a density of 0.45 to 0.57g/cm ³ and a compressive strength of 20 to 40MPa. It can be used in marine environments between 1,000 and 3,000 meters. Although the existing preparation methods can obtain low-density solid buoyancy materials, the addition of polymer hollow microspheres often reduces the modulus of the material. Water molecules tend to gradually penetrate into the material under pressure, and the water absorption rate continues to increase, resulting in solid buoyancy. When materials work underwater for a long time, they are prone to loss of buoyancy, and in severe cases, safety problems may occur. The addition of millimeter or centimeter-sized hollow balls will cause the machining performance of the solid buoyant material to be lost, and it can only be directly cast. Therefore, there is a need to develop a lightweight and high-strength solid buoyancy material that can achieve low density without losing the modulus and machinability of the solid buoyancy material.

Contents of the invention

An object of the present invention is to provide a lightweight and high-strength solid buoyancy material that adopts a low-density, low-viscosity epoxy vinyl ester resin system, which is beneficial to both the reduction of the density of the solid buoyancy material and the hollow glass in the solid buoyancy material. To increase the filling rate of microbeads, hollow glass microbeads with three particle sizes of large, medium and small are selected at the same time, and combined with high-frequency vacuum degassing technology, a lightweight and high-strength microbead with low density and no loss of modulus is obtained and is suitable for depths of Solid buoyant materials shallower than 4000 meters.

Another object of the present invention is to provide a method for preparing a lightweight and high-strength solid buoyancy material.

In order to achieve the above objects, the present invention adopts the following technical solutions:

In a first aspect, the present invention provides a lightweight and high-strength solid buoyancy material, including the following raw materials in parts by weight:

182.06-472.25 parts of polymer substrate system and 50-100 parts of hollow glass beads;

The viscosity of the polymer substrate system is 100-500 mPa·s, including 100 parts of epoxy vinyl ester resin, 20-100 parts of epoxidized polybutadiene, 20-80 parts of cross-linking agent, 20-100 parts Cross-linking monomer, 15-70 parts curing agent, 5-20 parts initiator, 0.05-0.2 parts accelerator, 0.01-0.05 parts polymerization inhibitor, 2 parts surface treatment agent;

The particle size of the hollow glass microspheres is 10-150 μm, the density is 0.10-0.30g/cm ³ , and the compressive strength is 2-20MPa.

The invention adopts a low-viscosity, low-density polymer base material system, which consists of epoxy vinyl ester resin, epoxidized polybutadiene, cross-linking agent, cross-linking monomer, curing agent, initiator and accelerator. , polymerization inhibitors and surface treatment agents. By adding a large amount of low-viscosity cross-linking agent and cross-linking monomer, the system effectively reduces the viscosity of the system and controls it between 100 and 500 mPa·s; in the system, low-density epoxidized polybutadiene and cross-linking monomer are introduced. It also effectively reduces the density of the cured material, with a value of 0.95-1.0g/cm ³ ; the use of low-viscosity, low-density polymer substrate systems lays a good foundation for the preparation of lightweight and high-strength solid buoyancy materials.

Optionally, the hollow glass microspheres include 10-30% of large spheres with a particle size of 80-150 μm, 50-70% of medium spheres with a particle size of 50-80 μm, and 10-20% by volume. % of beads with a particle size of 10-50 μm.

Selecting hollow glass microbeads of different particle sizes and adjusting their matching ratio will help improve the accumulation ability of the microbeads, thereby increasing their filling rate. During the high-frequency vibration process, the surface tension of the hollow glass microspheres is destroyed, and the possibility of agglomeration between microspheres of different particle sizes is reduced, which is conducive to the accumulation of microspheres; at the same time, the low-viscosity polymer substrate system cooperates with different particle sizes The use of hollow glass beads allows bubbles to migrate to the surface and escape, which is beneficial to obtaining a solid buoyant material without bubble defects and enhancing its compressive strength.

Optionally, the epoxy vinyl ester resin is selected from at least one of bisphenol A type epoxy vinyl ester resin, novolac type epoxy vinyl ester resin, and urethane type epoxy vinyl ester resin. .

Optionally, the cross-linking agent is selected from one of divinylbenzene, diallyl phthalate, and triallyl cyanurate.

Optionally, the cross-linking monomer is selected from one of methyl acrylate, ethyl acrylate, n-butyl acrylate, and tert-butyl acrylate.

Optionally, the curing agent is selected from the group consisting of methyltetrahydrophthalic anhydride and methylhexahydrophthalic anhydride.

Optionally, the initiator is selected from tert-butyl hydroperoxide, methyl isobutyl ketone peroxide, cumene hydroperoxide, di-tert-butyl peroxide, dicumyl peroxide, peroxide At least one of dilauroyl, dicyclohexyl peroxydicarbonate, tert-butyl peroxypivalate, methyl ethyl ketone peroxide, and cyclohexanone peroxide.

Optionally, the accelerator is cobalt isooctanoate or cobalt naphthenate;

Optionally, the polymerization inhibitor is one of p-benzoquinone, hydroquinone, tert-butylhydroquinone, and 2,6-di-tert-butyl-4-cresol.

Optionally, the surface treatment agent is a silane coupling agent, selected from γ-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane Silane, one of 3-methacryloyloxypropyltrimethoxysilane.

In a second aspect, the present invention provides a method for preparing the lightweight and high-strength solid buoyancy material, which includes the following steps:

(1) Mix epoxy vinyl ester resin, epoxidized polybutadiene, cross-linking agent, cross-linking monomer and curing agent evenly, then add initiator, accelerator, polymerization inhibitor and surface treatment while stirring agent; move it into a vacuum mixer, vacuum to -0.08~-0.1MPa, and stir at high speed; then add hollow glass beads, vacuum to -0.08~-0.1MPa, and continue stirring until uniformly mixed to obtain a vacuum mixture material;

(2) Pour the vacuum mixed material into the mold treated with the release agent, place it in a high-frequency vacuum vibration box, evacuate to -0.08~-0.1MPa, and vibrate for deaeration and densification; then program-controlled heating Solid buoyancy material is obtained by curing, demoulding and removing the surface layer.

Optionally, the vibration frequency in the high-frequency vacuum vibration box is 2000-10000Hz, and the vibration time is 3-5min;

Optionally, the program-controlled heating curing includes: a pre-curing stage maintained at a temperature of 25-60°C for 6-48 hours, a post-curing stage maintained at a temperature of 150-180°C for 2-12 hours, and a cooling rate of 2-5°C. /min cooling phase.

During the preparation process, the present invention also adopts high-frequency vibration vacuum degassing technology. When it is combined with a low-viscosity polymer system and a hollow glass microsphere system with high stacking capacity, it can achieve high filling of hollow glass microspheres in the polymer. , obtaining a material with densely packed microbeads, which also promotes the full elimination of microbubbles, and obtains products without defects such as bubbles.

The beneficial effects of the present invention are as follows:

The invention provides a lightweight and high-strength solid buoyancy material, which adopts a low-density, low-viscosity polymer base material system, is matched with a specific proportion of hollow glass beads of different particle sizes, and is prepared by using a high-frequency vacuum vibration method. It accelerates the detachment of bubbles and avoids material defects due to bubbles. It also increases the filling rate of hollow glass beads, ensuring the high modulus and machining performance of the material, and obtaining a lightweight and high-strength solid suitable for shallow depths of less than 4,000 meters. Buoyancy material.

Detailed ways

In order to make the technical solutions and advantages of the present invention clearer, the implementation of the present invention will be further described in detail below with reference to specific examples.

Example

Example 1

Weigh 100 parts of bisphenol A epoxy vinyl ester resin, 100 parts of epoxidized polybutadiene, 80 parts of divinylbenzene, 100 parts of tert-butyl acrylate, and 70 parts of methylhexahydrophthalic anhydride Mix well with mixer on high speed. Then, 20 parts of methyl ethyl ketone peroxide, 0.2 parts of cobalt isooctanoate, 0.05 parts of hydroquinone, and 2 parts of 3-glycidoxypropyltrimethoxysilane were added to the above mixture, and stirred for 10 minutes. Add the stirred mixture to the vacuum mixer, evacuate until the vacuum degree reaches -0.08~-0.1MPa, and continue stirring for 20 minutes to obtain a vacuum premix. The viscosity of the vacuum premix is 500mPa·s.

Three types of large, medium and small hollow glass microspheres with average particle sizes of 100μm, 60μm and 20μm were graded according to the volume ratio of 10:70:20 to obtain microspheres with an average density of 0.25g/cm ³ and a compressive strength of 20MPa. Bead system. Add 100 parts of the graded microbead system to the vacuum premix, evacuate, so that the vacuum degree in the stirring tank reaches -0.08~-0.1MPa, continue stirring at low speed for 40 minutes, so that the hollow glass microspheres and materials are fully mixed to obtain Mix materials under vacuum. The viscosity of the vacuum mixture material is 5000mPa·s.

Use an extruder to extrude the vacuum mixture material in the mixing kettle and pour it into a mold treated with a release agent, and then place the mold containing the vacuum mixture material in a special high-frequency vibration vacuum box for densification and release. Soaking treatment. The vacuum box is evacuated to -0.08~-0.1MPa, and then high-frequency vibration is turned on, with a vibration frequency of 5000Hz and vibration for 3 minutes.

Place the mold containing the degassed material in a blast drying oven and use programmed temperature control for heating and solidification. The temperature in the pre-curing stage is 25°C, maintained for 48 hours; the post-curing temperature is 180°C, maintained for 12 hours; the rate of the cooling stage is controlled at 5°C/min.

Eject the solidified module from the mold to obtain a solid buoyancy material blank block, and use machining to remove the surface layer to obtain a solid buoyancy material with a flat and smooth surface.

The solid buoyancy material prepared according to the above method has a density of 0.48g/cm ³ and a modulus of 3.0GPa. It has excellent machining performance and can be processed by cutting, drilling and other machining. In addition, the density of the cured product of the polymer substrate system is 0.97g/cm ³ and the density of the hollow glass microspheres is 0.25g/cm ³ . Calculation shows that the volume filling rate of the hollow glass microspheres is 68%.

The prepared solid buoyancy material has a density of 0.48g/cm ³ and a destruction strength of 68MPa. The compressive strength under the same density is significantly improved compared to the existing technology.

Example 2

Weigh 100 parts of urethane epoxy vinyl ester resin, 20 parts of epoxidized polybutadiene, 20 parts of triallyl cyanurate, 50 parts of n-butyl acrylate, and 15 parts of methyltetrahydrogen Mix the phthalic anhydride thoroughly with a high speed mixer. Then, add 10 parts of dicyclohexyl peroxydicarbonate, 0.1 part of cobalt naphthenate, 0.01 part of hydroquinone, and 2 parts of 3-methacryloyloxypropyltrimethoxysilane into the above mixture, and stir 5 minutes. Add the stirred mixture to the vacuum mixer, evacuate until the vacuum degree reaches -0.08~-0.1MPa, and continue stirring for 20 minutes to obtain a vacuum premix. The viscosity of the vacuum premix is 100mPa·s.

Three types of large, medium, and small hollow glass microspheres with average particle sizes of 120 μm, 70 μm, and 30 μm were graded in a volume ratio of 20:60:20 to obtain microspheres with an average density of 0.15g/cm ³ and a compressive strength of 10MPa. Bead system. Add 50 parts of the graded microbead system to the vacuum premix, evacuate, so that the vacuum degree in the stirring tank reaches -0.08 ~ -0.1MPa, continue stirring at low speed for 40 minutes, so that the hollow glass microspheres and materials are fully mixed to obtain Mix materials under vacuum. The viscosity of the vacuum mixture material is 1000mPa·s.

Use an extruder to extrude the vacuum mixture material in the mixing kettle and pour it into a mold treated with a release agent, and then place the mold containing the vacuum mixture material in a special high-frequency vibration vacuum box for densification and release. Soaking treatment. The vacuum box is evacuated to -0.08~-0.1MPa, and then high-frequency vibration is turned on, with a vibration frequency of 10000Hz and vibration for 10 minutes.

Place the mold containing the degassed material in a blast drying oven and use programmed temperature control for heating and solidification. The temperature in the pre-curing stage is 60°C, maintained for 6 hours; the post-curing temperature is 150°C, maintained for 4 hours; the cooling stage rate is controlled at 2°C/min.

Eject the solidified module from the mold to obtain a solid buoyancy material blank block, and use machining to remove the surface layer to obtain a solid buoyancy material with a flat and smooth surface.

The solid buoyancy material prepared according to the above method has a density of 0.40g/cm ³ and a modulus of 2.5GPa. It has excellent machining performance and can be processed by cutting, drilling and other machining. The density of the cured product of the epoxy vinyl ester resin system is 1.0g/cm ³ and the density of the hollow glass beads is 0.15g/cm ³ . Calculation shows that the volume filling rate of the hollow glass beads is 70%.

The prepared solid buoyancy material has a density of 0.40g/cm ³ and a destruction strength of 38MPa. The compressive strength under the same density is significantly improved compared to the existing technology.

Example 3

Weigh 100 parts of phenolic epoxy vinyl ester resin, 100 parts of epoxidized polybutadiene, 20 parts of diallyl phthalate, 100 parts of methyl acrylate, and 70 parts of methyl hexahydrophthalic anhydride Mix well with mixer on high speed. Then, 10 parts of dicyclohexyl peroxydicarbonate, 0.05 parts of cobalt naphthenate, 0.02 parts of hydroquinone, and 2 parts of γ-aminopropyltrimethoxysilane were added to the above mixture, and stirred for 5 minutes. Add the stirred mixture to the vacuum mixer, evacuate until the vacuum degree reaches -0.08~-0.1MPa, and continue stirring for 20 minutes to obtain a vacuum premix. The viscosity of the vacuum premix is 300mPa·s.

Three types of large, medium and small hollow glass microspheres with average particle sizes of 120μm, 70μm and 20μm were graded in a volume ratio of 30:50:20 to obtain microspheres with an average density of 0.12g/cm ³ and a compressive strength of 5MPa. Bead system. Add 50 parts of the graded microbead system to the vacuum premix, evacuate, so that the vacuum degree in the stirring tank reaches -0.08 ~ -0.1MPa, continue stirring at low speed for 40 minutes, so that the hollow glass microspheres and materials are fully mixed to obtain Mix materials under vacuum. The viscosity of the vacuum mixture material is 3000mPa·s.

Use an extruder to extrude the vacuum mixture material in the mixing kettle and pour it into a mold treated with a release agent, and then place the mold containing the vacuum mixture material in a special high-frequency vibration vacuum box for densification and release. Soaking treatment. The vacuum box is evacuated to -0.08~-0.1MPa, and then high-frequency vibration is turned on, with a vibration frequency of 10000Hz and vibration for 5 minutes.

Place the mold containing the degassed material in a blast drying oven and use programmed temperature control for heating and solidification. The temperature in the pre-curing stage is 50°C, maintained for 24 hours; the post-curing temperature is 180°C, maintained for 8 hours; the rate of the cooling stage is controlled at 2°C/min.

Eject the solidified module from the mold to obtain a solid buoyancy material blank block, and use machining to remove the surface layer to obtain a solid buoyancy material with a flat and smooth surface.

The solid buoyancy material prepared according to the above method has a density of 0.35g/cm ³ and a modulus of 2.0GPa. It has excellent machining performance and can be processed by cutting, drilling and other machining. The density of the cured product of the epoxy vinyl ester resin system is 0.95g/cm ³ and the density of the hollow glass beads is 0.12g/cm ³ . Calculation shows that the volume filling rate of the hollow glass beads is 72%.

The density of the prepared solid buoyant material is 0.35g/cm ³ and the destruction strength is 20MPa. At the same density, the compressive strength is significantly improved compared to the existing technology.

Obviously, the above-mentioned embodiments of the present invention are only examples to clearly illustrate the present invention, and are not intended to limit the implementation of the present invention. For those of ordinary skill in the art, based on the above description, they can also make There are other different forms of changes or modifications, and it is impossible to exhaustively enumerate all the embodiments here. All obvious changes or modifications derived from the technical solution of the present invention are still within the protection scope of the present invention.

Claims (11)

1. A lightweight and high-strength solid buoyancy material, characterized in that it includes the following raw materials in parts by weight: 182.06-472.25 parts of polymer substrate system and 50-100 parts of hollow glass beads; The viscosity of the polymer substrate system is 100-500 mPa·s, including 100 parts of epoxy vinyl ester resin, 20-100 parts of epoxidized polybutadiene, 20-80 parts of cross-linking agent, 20-100 parts Cross-linking monomer, 15-70 parts curing agent, 5-20 parts initiator, 0.05-0.2 parts accelerator, 0.01-0.05 parts polymerization inhibitor, 2 parts surface treatment agent; The particle size of the hollow glass microspheres is 10-150 μm, the density is 0.10-0.30g/cm ³ , and the compressive strength is 2-20MPa; Calculated by volume proportion, the hollow glass microspheres include 10-30% large spheres with a particle size of 80-150 μm, 50-70% medium spheres with a particle size of 50-80 μm, and 10-20% small particles. For small balls of 10-50μm; The cross-linking monomer is selected from one of methyl acrylate, ethyl acrylate, n-butyl acrylate, and tert-butyl acrylate; The surface treatment agent is a silane coupling agent; The preparation method of the lightweight high-strength solid buoyancy material includes the following steps: (1) Mix epoxy vinyl ester resin, epoxidized polybutadiene, cross-linking agent, cross-linking monomer, and curing agent evenly, and add initiator, accelerator, polymerization inhibitor and surface treatment while stirring. agent; move it into a vacuum mixer, vacuum to -0.08~-0.1MPa, and stir at high speed; then add hollow glass beads, vacuum to -0.08~-0.1MPa, and continue stirring until uniformly mixed to obtain a vacuum mixture material; (2) Pour the vacuum mixed material into the mold treated with the release agent, place it in a high-frequency vacuum vibration box, evacuate to -0.08 ~ -0.1MPa, vibrate for deaeration and densification; then program-controlled heating Solid buoyancy material is obtained by curing, demoulding and removing the surface layer. 2. The lightweight and high-strength solid buoyancy material according to claim 1, wherein the epoxy vinyl ester resin is selected from the group consisting of bisphenol A-type epoxy vinyl ester resin and phenolic-type epoxy vinyl ester resin. At least one kind of urethane type epoxy vinyl ester resin. 3. The lightweight and high-strength solid buoyancy material according to claim 1, characterized in that the cross-linking agent is selected from the group consisting of divinylbenzene, diallyl phthalate, and triallyl cyanurate. kind of. 4. The lightweight and high-strength solid buoyancy material according to claim 1, characterized in that the curing agent is selected from one of methyltetrahydrophthalic anhydride and methylhexahydrophthalic anhydride. 5. The lightweight and high-strength solid buoyancy material according to claim 1, wherein the initiator is selected from the group consisting of tert-butyl hydroperoxide, methyl isobutyl ketone peroxide, and cumene hydroperoxide. At least one of di-tert-butyl peroxide, dicumyl peroxide, dilauroyl peroxide, dicyclohexyl dicarbonate peroxide, tert-butyl pivalate peroxide, methyl ethyl ketone peroxide, and cyclohexanone peroxide A sort of. 6. The lightweight and high-strength solid buoyancy material according to claim 1, wherein the accelerator is cobalt isooctanoate or cobalt naphthenate. 7. The lightweight and high-strength solid buoyancy material according to claim 1, characterized in that the polymerization inhibitor is p-quinone, hydroquinone, tert-butylhydroquinone, 2,6-di-tert-butyl One of the base-4-cresols. 8. The lightweight and high-strength solid buoyancy material according to claim 1, characterized in that the silane coupling agent is selected from the group consisting of γ-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3 -Glycidyloxypropyltrimethoxysilane, one of the 3-methacryloyloxypropyltrimethoxysilane. 9. A method for preparing a lightweight high-strength solid buoyancy material as claimed in any one of claims 1 to 8, characterized in that it includes the following steps: (1) Mix epoxy vinyl ester resin, epoxidized polybutadiene, cross-linking agent, cross-linking monomer, and curing agent evenly, and add initiator, accelerator, polymerization inhibitor and surface treatment while stirring. agent; move it into a vacuum mixer, vacuum to -0.08~-0.1MPa, and stir at high speed; then add hollow glass beads, vacuum to -0.08~-0.1MPa, and continue stirring until uniformly mixed to obtain a vacuum mixture material; (2) Pour the vacuum mixed material into the mold treated with the release agent, place it in a high-frequency vacuum vibration box, evacuate to -0.08 ~ -0.1MPa, vibrate for deaeration and densification; then program-controlled heating Solid buoyancy material is obtained by curing, demoulding and removing the surface layer. 10. The preparation method according to claim 9, characterized in that the vibration frequency in the high-frequency vacuum vibration box is 2000-10000 Hz, and the vibration time is 3-5 minutes. 11. The preparation method according to claim 9, characterized in that the program-controlled heating and curing includes: a pre-curing stage maintained at a temperature of 25-60°C for 6-48h, and a temperature maintained at a temperature of 150-180°C for 2-12h. Post-curing stage, and cooling stage with a cooling rate of 2-5°C/min.