CN111019340B

CN111019340B - Polysorbate/T-ZnOw/oil-containing cast nylon composite material

Info

Publication number: CN111019340B
Application number: CN201911352247.9A
Authority: CN
Inventors: 王月欣; 王宇昕; 冯琪; 张倩
Original assignee: Hebei University of Technology
Current assignee: Hebei University of Technology
Priority date: 2019-12-25
Filing date: 2019-12-25
Publication date: 2022-04-12
Anticipated expiration: 2039-12-25
Also published as: CN111019340A

Abstract

The invention relates to a polysorbate/T-ZnOw/oil-containing cast nylon composite material. The composite material comprises, by weight, 100 parts of caprolactam, 0.01-1.0 part of polysorbate, 0.05-2.0 parts of tetrapod-shaped zinc oxide whisker (T-ZnOw), 1-8 parts of lubricating oil, 0.07-0.5 part of catalyst and 0.3-0.5 part of activator. The invention improves the mechanical property and the friction property of the oil-containing cast nylon by adding the new additive polysorbate, and has the advantages of simple preparation process, low polysorbate cost, small dosage and obvious modification effect.

Description

Polysorbate/T-ZnOw/oil-containing cast nylon composite material

Technical Field

The invention belongs to the technical field of polymer composite materials, and discloses an oil-containing cast nylon composite material modified by polysorbate and an inorganic filler.

Background

The cast nylon (MC nylon 6) is an engineering plastic with wide application, and compared with the common nylon 6, the cast nylon (MC nylon 6) has the advantages of simple process, low cost, unlimited molding size, high molecular weight, high crystallinity, high mechanical strength, wear resistance, chemical corrosion resistance, wide application temperature range and wide application. At present, cast nylon is used as parts such as carrier rollers, gears, sliding blocks and the like in many domestic industrial and mining enterprises and special equipment, however, under the condition of not adding any additive, the cast nylon cannot bear the work of high load and high rotating speed, and polymers are sensitive to temperature in the using process, so that not only can the surface be melted to generate adhesive wear, but also slight looseness can be generated under the action of force due to the aggregation of frictional heat, and the application of the cast nylon is severely restricted.

Cast nylon is modified by the addition of lubricants in order to adapt it to more severe friction conditions. For example, the Chinese invention patent CN1140130A discloses an oil-containing cast nylon added with silicone oil, and the friction performance of the composite material is improved. The Chinese invention patent CN106432714A discloses a toughened wear-resistant MC nylon/liquid paraffin composite material. However, the liquid second-phase lubricant has poor compatibility with the nylon matrix and very low strength, which is equivalent to the formation of liquid pores in the material, so that the internal stress of the material is concentrated, the plastic deformation resistance is reduced, the strength is reduced, and the current requirements cannot be met.

Aiming at the common problem of poor mechanical property of the oil-containing cast nylon, an oil-containing cast nylon composite material which has certain strength and toughness and is wear-resistant is urgently needed to be sought.

Disclosure of Invention

The invention provides a polysorbate/tetrapod zinc oxide whisker (T-ZnOw)/oil-containing cast nylon composite material aiming at the defects of the existing oil-containing cast nylon. The composite material is prepared by taking polyamide as a matrix, lubricating oil, polysorbate and T-ZnOw as additives and adopting caprolactam in-situ anion polymerization, and the mechanical property and the friction property of the oil-containing cast nylon are improved by adding the new additive polysorbate. The preparation process is simple, the polysorbate is low in cost and dosage, and the modification effect is obvious.

The technical scheme of the invention is as follows:

a polysorbate/T-ZnOw/oil-containing cast nylon composite material is characterized in that: the catalyst comprises, by weight, 100 parts of caprolactam, 0.01-1.0 part of polysorbate, 0.05-2.0 parts of tetrapod-like zinc oxide whisker (T-ZnOw), 1-8 parts of lubricating oil, 0.07-0.5 part of catalyst and 0.3-0.5 part of activator.

The polysorbate is one or more of polyoxyethylene sorbitan monolaurate (polysorbate 20), polyoxyethylene sorbitan monopalmitate (polysorbate 40), polyoxyethylene sorbitan monostearate (polysorbate 60) and polyoxyethylene sorbitan monooleate (polysorbate 80).

The catalyst is one or more of sodium hydroxide, sodium methoxide and sodium ethoxide.

The activating agent is one or more of toluene-2, 4-diisocyanate, diphenylmethane diisocyanate and hexamethylene diisocyanate.

The preparation method of the polysorbate/T-ZnOw/oil-containing cast nylon composite material comprises the following steps:

according to the proportion, melting a caprolactam monomer, heating to 120-130 ℃, adding a catalyst, vacuumizing for dehydration, heating to 138-142 ℃, and adding a mixed dispersion of lubricating oil, polysorbate and T-ZnOw; and (3) after uniformly mixing, adding an activating agent at 135-145 ℃, injecting into a mold at 160-170 ℃, and polymerizing for 15-30 min to finally obtain the composite material.

The invention has the beneficial effects that:

according to the invention, the polysorbate is added into the system, so that oil drops are dispersed in the polymer matrix more uniformly, the diameter of the oil drops is smaller, the specific surface area of the oil drops is increased, when the oil-containing cast nylon and the counter part rub, the contact area of the counter part and the oil drops is increased, the friction coefficient is reduced, and compared with the T-ZnOw/oil-containing cast nylon composite material, the friction coefficient is reduced by 40% by only adding 0.05g of the polysorbate. And the polysorbate also plays a role of a cocatalyst while improving the compatibility of oil drops and a matrix, so that a nylon molecular chain is partially crosslinked through the polysorbate, the mechanical property of the oil-containing cast nylon is greatly improved, and compared with the T-ZnOw/oil-containing cast nylon composite material, the tensile strength, the compression strength, the bending strength and the modulus of the material are improved to different degrees by only adding 0.05g of the polysorbate, and the abrasion loss is also obviously reduced. Wherein, the tensile strength is improved by 10.3%, the tensile modulus is improved by 21.2%, the compressive strength is improved by 32.9%, the compressive modulus is improved by 20.1%, the bending strength is improved by 18.5%, the bending modulus is improved by 17.8%, and the abrasion loss is reduced by 34.8%.

Detailed Description

In order to make those skilled in the art better understand and implement the technical solution of the present invention, the following description is given for clear and complete description of the technical solution of the present invention with reference to specific examples. Laboratory equipment conventional in the art is used in the following examples. The various starting materials used in the following examples, unless otherwise specified, were conventional commercially available products.

The tetrapod-like zinc oxide whiskers were commercially available materials, and the tetrapod-like zinc oxide whiskers used in the following examples were specifically purchased from kyoto university crystal science co.

Example 1:

(1) adding 0.02g of polysorbate 80 into 4.00g of SN400 lubricating oil to obtain yellow transparent liquid; 0.10g of dried T-ZnOw was added thereto, and sufficiently shaken to obtain a mixed dispersion.

(2) Heating 100g of caprolactam to 80 ℃ for melting, heating to 128 ℃, adding 0.20g of NaOH, vacuumizing for removing water for 5-8 min, heating to 140 ℃, and adding the mixed dispersion liquid obtained in the step (1).

(3) And after uniformly mixing, adding 0.35g of toluene-2, 4-diisocyanate at 142 ℃, fully shaking to obtain mixed active liquid, immediately injecting into a die at 165 ℃, carrying out anion ring-opening polymerization, maintaining at 165 ℃ for 30min, automatically cooling to room temperature, and demolding to obtain the polysorbate 80/T-ZnOw/oil-containing cast nylon composite material.

Comparative example:

(1) 0.10g of dried T-ZnOw is added into 4.00g of SN400 lubricating oil and sufficiently shaken to obtain a mixed dispersion liquid.

(3) After uniform mixing, adding 0.35g of toluene-2, 4-diisocyanate at 142 ℃, fully shaking to obtain mixed active liquid, immediately injecting into a die at 165 ℃ for anion ring-opening polymerization, maintaining at 165 ℃ for 30min, automatically cooling to room temperature, and demolding to obtain the T-ZnOw/oil-containing cast nylon composite material.

The mechanical properties and frictional properties test results of example 1 and comparative example are shown in the attached table 1. And (3) testing the mechanical property of the experimental sample strip by using a CMT-6104 universal testing machine, and testing the frictional wear property of the experimental sample strip by using an M-200 frictional wear testing machine.

The test criteria are as follows:

appendix 1 polysorbate 80/T-ZnOw/oil-containing cast nylon composite material performance test

As can be seen from the data in the attached table 1, compared with the T-ZnOw/oil-containing cast nylon composite material, after the polysorbate 80 is added, various mechanical properties of the prepared composite material are improved to different degrees, and the friction coefficient and the abrasion loss are also obviously reduced.

Example 2:

the mass of polysorbate 80 in step (1) was changed to 0.05g, and the other steps were referred to example 1.

The performance test result is slightly improved compared with the example 1, and the performance data is shown in the attached table 2.

Appendix 2 polysorbate 80/T-ZnOw/oil-containing cast nylon composite performance test

Example 3:

polysorbate 80 in step (1) was replaced with polysorbate 20 with a mass of 0.02g, and the other steps were referred to example 1. The performance test results are similar to those of example 1.

Example 4:

polysorbate 80 in step (1) was replaced with polysorbate 60 with a mass of 0.02g, and the other steps were referred to example 1. The performance test results are similar to those of example 1.

Example 5:

polysorbate 80 in step (1) was replaced with a mixture of 0.01g polysorbate 20 and 0.01g polysorbate 40, and the other steps were referenced to example 1. The performance test results are similar to those of example 1.

Example 6:

polysorbate 80 in step (1) was replaced with a mixture of 0.01g polysorbate 60, 0.02g polysorbate 40 and 0.02g polysorbate 20, the other steps being with reference to example 1. The performance test result is similar to that of example 2.

The mechanism of the invention is as follows: the polysorbate used in the invention has two functions in the system: the polysorbate is used as a nonionic surfactant, so that the interfacial tension of an oil phase and a nylon phase can be reduced, oil drops are dispersed in a nylon matrix more uniformly, and an interfacial film is formed to enhance the interfacial interaction between the oil drops and the nylon matrix; and secondly, because the polysorbate has three extended hydrophilic hydroxyl groups, the polysorbate can react with an isocyanate group of an activating agent in the polymerization process, so that the polysorbate has an isocyanate group and plays a role of a cocatalyst, the monomer is initiated to be polymerized to form a macromolecular chain, partial crosslinking is generated among the macromolecular chains, and the mechanical property of the material is improved.

The method adopts completely same preparation conditions and processes, only changes the type and the content of the polysorbate, and finds that the mechanical property and the friction property of the polysorbate/T-ZnOw/oil-containing cast nylon composite material are obviously improved along with the increase of the content of the polysorbate.

The invention is not the best known technology.

Claims

1. The polysorbate/T-ZnOw/oil-containing cast nylon composite material is characterized by comprising 100 parts by weight of caprolactam, 0.01-1.0 part by weight of polysorbate, 0.05-2.0 parts by weight of tetrapod-like zinc oxide whisker (T-ZnOw), 1-8 parts by weight of lubricating oil, 0.07-0.5 part by weight of catalyst and 0.3-0.5 part by weight of activator;

the polysorbate is one or more of polyoxyethylene sorbitan monolaurate (polysorbate 20), polyoxyethylene sorbitan monopalmitate (polysorbate 40), polyoxyethylene sorbitan monostearate (polysorbate 60) and polyoxyethylene sorbitan monooleate (polysorbate 80);

the catalyst is specifically one or more of sodium hydroxide, sodium methoxide and sodium ethoxide;

2. The method of preparing the polysorbate/T-ZnOw/oil containing cast nylon composite of claim 1, comprising the steps of:

melting caprolactam monomer according to the proportion of claim 1, heating to 120-130 ℃, adding a catalyst, vacuumizing for dehydration, heating to 138-142 ℃, and adding a mixed dispersion of lubricating oil, polysorbate and T-ZnOw; and (3) after uniformly mixing, adding an activating agent at 135-145 ℃, injecting into a mold at 160-170 ℃, and polymerizing for 15-30 min to finally obtain the composite material.