CN103713009B - The assay method of thermal expansivity - Google Patents

Abstract

The present invention relates to a kind of assay method of thermal expansivity.This assay method comprise determine testing sample change by unit temperature the spectrum peak amount of movement caused, count χ _f; Testing sample and polymkeric substance are carried out being mixed to get potpourri, potpourri ultrasonic disperse is obtained compound substance; Second spectral value of compound substance under surface strain values is measured with device for measurement of strain and with spectroscopic system, surface strain values and the second spectral value are carried out linear fit, determine testing sample caused by unit strain, being parallel to should nyctitropic spectrum peak amount of movement, counts S ₀; What measure testing sample in compound substance determination compound substance with spectroscopic system changes by unit temperature the spectrum peak amount of movement caused, and counts χ _c; If the thermalexpansioncoefficientα of polymkeric substance _eknown, then the thermalexpansioncoefficientα of testing sample can be calculated according to following formula _f: α _f=α _e-(χ _c-χ _f)/S ₀.This assay method is simple, and it is convenient to measure, and can measure the thermal expansivity of testing sample comparatively quickly and accurately.

Description

The assay method of thermal expansivity

Technical field

The present invention relates to material parameter determination techniques field, particularly relate to a kind of assay method of thermal expansivity.

Background technology

Carbon nanomaterial, if carbon nano-tube, Graphene etc. are due to the physicochemical property of its excellence, has broad application prospects.For in materials processing forming process or the occasion that under working condition, temperature variation is larger, will unrelieved stress be caused to produce if the matrix thermal expansivity that carbon nanomaterial is in contact with it does not mate, two alternate generation interface slidings can be made time serious or peel off.But the measurement of the thermal expansivity of carbon nanomaterial is a difficult problem for puzzlement science and industry member always.

What thermal linear expansion coefficient described is the ratio that unit temperature changes material elongation amount and the raw footage caused, and namely strains.The strain variation with temperature relation of direct measurement carbon nanomaterial is very difficult.Up to now, the strain variation with temperature relation of carbon nanomaterial is determined primarily of theory calculate, but differs greatly based on the result that various theoretical model is predicted, expands or shrink to there is no final conclusion when at room temperature carbon nanomaterial is heated.The measuring means developed now mainly measure crystallite dimension variation with temperature by X-ray diffraction, and this method precision is high, but can working sample little, finding speed slow, instrument complex and expensive.Equally, a large amount of solvent based polymer slurries of semicon industry are finally all processed into the form of film, cannot prepare the block sample of regular shape, and the thermal expansivity that measure these materials also needs the more succinct assay method efficiently of exploitation.The thermal expansivity of exploitation Quick Measurement carbon nanomaterial and polymer thin-film material has important scientific meaning and application background.

Summary of the invention

Based on this, be necessary the assay method that a kind of thermal expansivity is provided, to measure the thermal expansivity of the material such as carbon nanomaterial or polymkeric substance quickly and accurately.

An assay method for thermal expansivity, comprises the steps:

Measure the spectrum of testing sample under different temperatures value respectively and obtain multiple first spectral value, described different temperatures value and described multiple first spectral value are carried out linear fit, that determines described testing sample changes by unit temperature the spectrum peak amount of movement caused, and counts χ _f;

Described testing sample and polymkeric substance are carried out being mixed to get potpourri, described potpourri ultrasonic disperse is obtained compound substance;

Different deformation is applied to described compound substance, multiple surface strain values of described compound substance are measured with device for measurement of strain, and the spectrum of testing sample under different surface strain values measured in described compound substance obtains multiple second spectral value, described multiple surface strain values and described multiple second spectral value are carried out linear fit, determine described testing sample caused by unit strain, being parallel to should nyctitropic spectrum peak amount of movement, counts S ₀;

The spectrum of testing sample under different temperatures value measured in described compound substance obtains multiple 3rd spectral value, described different temperatures value and described multiple 3rd spectral value are carried out linear fit, that determines the testing sample in described compound substance changes by unit temperature the spectrum peak amount of movement caused, and counts χ _c; And

The thermal expansivity of described testing sample is obtained according to following formulae discovery:

α _F=α _E-(χ _C-χ _F)/S ₀；

Wherein, described α _frepresent the thermal expansivity of described testing sample, described α _efor the thermal expansivity of described polymkeric substance;

Described first spectral value, the second spectral value and the 3rd spectral value are Raman light spectrum, fluorescence emission spectrum or infrared light spectrum.

Wherein in an embodiment, describedly measure the step that the spectrum of testing sample under different temperatures value obtains multiple first spectral value respectively and be specially: be 10 DEG C with step-length, measure described testing sample respectively and obtain multiple first spectral value to the multiple spectrum under multiple temperature values of the temperature of the glass transition temperature 60 DEG C higher than described polymkeric substance from 22 DEG C.

Wherein in an embodiment, described polymkeric substance is epoxy resin, phenolics, polystyrene, PPTA, polyethylene terephthalate, polybenzimidazoles, polyetheretherketone or polyimide.

Wherein in an embodiment, in described potpourri, the mass ratio of described testing sample and polymkeric substance is 1:50 ~ 1:5000.

Wherein in an embodiment, it is 0.5 hour ~ 24 hours by the time of described potpourri ultrasonic disperse.

Wherein in an embodiment, described different deformation is applied to described compound substance, the step measuring multiple surface strain values of described compound substance with device for measurement of strain is specially: cut into strip resin by after described polymer cure, and described compound substance is coated on before solidification the surface of described strip resin, coating is formed on the surface of described strip resin after described composite material solidification, foil gauge is sticked at the edge of described coating, described foil gauge is electrically connected with described device for measurement of strain, applies different deformation to described strip resin.

Wherein in an embodiment, the scope described strip resin being applied to deformation is 0 ~ 0.4%, and step-length is 0.04%.

Wherein in an embodiment, the step that the spectrum of testing sample under different temperatures value in the described compound substance of described mensuration obtains multiple 3rd spectral value is specially: be 10 DEG C with step-length, measures testing sample in described compound substance respectively and obtain multiple 3rd spectral value to the multiple spectrum under multiple temperature values of the temperature of the glass transition temperature 60 DEG C higher than described polymkeric substance from 22 DEG C.

Wherein in an embodiment, the thermalexpansioncoefficientα of described polymkeric substance _emeasure as follows:

Measure the spectral value that the spectrum of fibrous material under different temperatures value obtains multiple fibrous material respectively, the spectral value of described different temperatures value and described multiple fibrous material is carried out linear fit, that determines described fibrous material changes by unit temperature the spectrum peak amount of movement caused, and counts χ _f1;

Cut into strip resin by after described polymer cure, described fibrous material is positioned on described strip resin, and separately takes described polymkeric substance, the described polymkeric substance separately taken is coated on described fibrous material before solidification, after solidification, obtains compound;

Different deformation is applied to described compound, the multiple surface strain values of described compound is measured with device for measurement of strain, and the multiple spectral values of the fibrous material measured in described compound under different surface strain values obtain the first spectral value of the fibrous material in multiple compound, first spectral value of the fibrous material in described multiple surface strain values and described multiple compound is carried out linear fit, determine that the unit strain of described fibrous material causes, being parallel to should nyctitropic spectrum peak amount of movement, counts S ₀₁;

The spectrum of fibrous material under different temperatures value measured in described compound obtains the second spectral value of the fibrous material in multiple compound, second spectral value of the fibrous material in described different temperatures value and described multiple compound is carried out linear fit, that determines the fibrous material in described compound changes by unit temperature the spectrum peak amount of movement caused, and counts χ _c1; And

The thermal expansivity of described polymkeric substance is calculated according to following formula:

α _E1=α _F1+(χ _C1-χ _F1)/S ₀₁；

Wherein, described α _e1represent the thermal expansivity of described polymkeric substance, described α _f1for the thermal expansivity of described fibrous material;

Second spectral value of the fibrous material in the first spectral value of the fibrous material in the spectral value of described multiple fibrous material, multiple compound and multiple compound is Raman light spectrum, fluorescence emission spectrum or infrared light spectrum.

Wherein in an embodiment, described fibrous material is alumina fibre, carbon fiber or aramid fiber.

The assay method of above-mentioned thermal expansivity is based on the thermal expansivity of Raman spectrum, fluorescence emission spectrum or infrared spectrometry testing sample.The spectrum measuring the testing sample in the spectrum variation with temperature of testing sample, polymeric matrix varies with temperature three parameters with temperature with the spectrum of the testing sample in the change strained and polymeric matrix, can calculate the thermal expansivity of testing sample.The assay method of this thermal expansivity is simple, and it is convenient to measure, and can measure the thermal expansivity of testing sample comparatively quickly and accurately.

Accompanying drawing explanation

Fig. 1 is the process flow diagram of the assay method of the thermal expansivity of an embodiment;

Fig. 2 is the schematic diagram measuring Raman spectrum by Raman system;

Fig. 3 is the Raman spectrum of alumina fibre when different temperatures of embodiment 1;

Fig. 4 is the graph of a relation of the Raman spectrum peak-to-peak value variation with temperature of the alumina fibre of embodiment 1;

Fig. 5 is the Raman spectrum of alumina fibre when different deformation in the compound of embodiment 1;

Fig. 6 is the Raman spectral peaks peak position of alumina fibre in the compound of embodiment 1 and the graph of a relation of strain;

Fig. 7 is the Raman spectrum of alumina fibre when different temperatures in the compound of embodiment 1;

Fig. 8 is the temperature variant graph of a relation of Raman spectral peaks peak position of the alumina fibre in the compound of embodiment 1;

Fig. 9 is Raman spectral peaks (G ' peak) the variation with temperature graph of a relation of the Single Walled Carbon Nanotube of embodiment 2;

Figure 10 is Raman spectral peaks (G ' peak) frequency of Single Walled Carbon Nanotube in the compound substance of embodiment 2 and the graph of a relation of strain;

Figure 11 is the temperature variant graph of a relation of Raman spectral peaks (G ' peak) frequency of the Single Walled Carbon Nanotube in the compound substance of embodiment 2.

Embodiment

For enabling above-mentioned purpose of the present invention, feature and advantage become apparent more, are described in detail the specific embodiment of the present invention below in conjunction with accompanying drawing.Set forth a lot of detail in the following description so that fully understand the present invention.But the present invention can be much different from alternate manner described here to implement, those skilled in the art can when without prejudice to doing similar improvement when intension of the present invention, therefore the present invention is by the restriction of following public concrete enforcement.

Nano material is distributed in polymkeric substance and makes compound substance.When the temperature of compound substance changes, because the thermal expansivity between polymkeric substance and nano material there are differences, make nano material produce deformation, temperature variation and deformation two combined factors cause the amount of movement Δ ω of the spectrum peak of nano material _{g '}can describe with following formula:

$\mathrm{\Δ}{\mathrm{\ω}}_{G^{\′}}=\mathrm{\Δ}{\mathrm{\ω}}_{G^{\′}}^T+\mathrm{\Δ}{\mathrm{\ω}}_{G^{\′}}^S---\left(1\right).$

(1) in formula, for the spectrum peak amount of movement that pure temperature variation causes, the spectrum peak causing nano material generation deformation then to cause for temperature variation moves.These two parameters are determined by following two formula respectively:

$\mathrm{\Δ}{\mathrm{\ω}}_{G^{\′}}^T={\mathrm{\χ}}_F\×\mathrm{\ΔT}---\left(2\right);$ $\mathrm{\Δ}{\mathrm{\ω}}_{G^{\′}}^S=S_0\×({\mathrm{\α}}_E-{\mathrm{\α}}_F)\×\mathrm{\ΔT}---\left(3\right).$

(2) and in (3) formula, χ _ffor the nano material spectrum peak amount of movement that unit temperature causes, α _efor the thermal expansivity of polymkeric substance, α _ffor the thermal expansivity of nano material.S ₀cause for unit strain, being parallel to should the spectrum peak amount of movement of nyctitropic nano material.

Take nano material as carbon nano-tube be example, as guided without external force, carbon nano-tube disperse state is in the polymer random orientation, when adopting spectroscopic system directly to measure compound substance containing random orientation carbon nano-tube and polymkeric substance to the response strained, also need the actual loading situation considering the carbon nano-tube formed an angle with external force, and the carbon nano-tube of different orientation is to the difference of spectrum peak intensity contribution, consider this 2 effects, S ₀can be described by following formula:

$S_0=\frac{{\∫}_0^{\mathrm{\π}}{\cos }^4\×({\cos }^2\mathrm{\θ}-v{\sin }^2\mathrm{\θ})\mathrm{d\θ}}{{\∫}_0^{\mathrm{\π}}{\cos }^4\mathrm{\θd\θ}}\×S\left(0\right)---\left(4\right).$

In formula, v is Poisson's coefficient, and θ is the angle of carbon nano-tube and external force, that S (0) causes for unit strain, containing the spectrum peak amount of movement of the compound substance of random orientation carbon nano-tube.

V is that material is intrinsic.θ is intermediate variable, does not exist after integration.

Formula (2) and (3) are substituted into formula (1), and arrangement obtains:

△ω _G′=χ _F×△T+S ₀×(α _E-α _F)×△T （5）。

Δ ω _{g '}also can be described by following formula:

Δω _G′=χ _C×ΔT （6）。

In formula, χ _cfor the amount of movement being changed the spectrum peak caused by unit temperature of carbon nanomaterial in compound substance, by measuring.

Be updated in (5) by formula (6), distortion arrangement obtains:

α _F=α _E-(χ _C-χ _F)/S ₀（7）。

In formula:

α _ffor the thermal expansivity of nano material;

α _efor the thermal expansivity of polymkeric substance.

Based on above-mentioned formula (7), obtaining α _ewhen, based on the thermal expansivity of spectroscopic assay nano material, particularly can measure carbon nanomaterial, as the thermal expansivity of carbon nano-tube, Graphene, carbon nano-fiber etc.Based on spectrum, by the thermal expansivity of above-mentioned formula (7) Quick Measurement carbon nanomaterial, solve and be difficult at present to measure the thermal expansivity of carbon nanomaterial or finding speed is slow and the science of instrument complex and expensive and an industry member difficult problem.

Above-mentioned spectrum can be Raman spectrum, fluorescence emission spectrum or infrared spectrum.

Refer to Fig. 1, the assay method of the thermal expansivity of an embodiment, comprises the steps S110 ~ S150.

Step S110: measure the spectrum of testing sample under different temperatures value respectively and obtain multiple first spectral value, different temperatures value and multiple first spectral value are carried out linear fit, and that determines testing sample changes by unit temperature the spectrum peak amount of movement caused, and counts χ _f.

Testing sample can be the materials such as carbon nano-tube, Graphene, carbon nano-fiber.

First spectral value can be Raman spectrum, fluorescence emission spectrum or infrared spectrum.

For the first spectral value for Raman spectrum, please refer to Fig. 2, warm table 10 is positioned on objective table 20, and testing sample (in Fig. 2, label is 40) is placed on warm table 10 heats, testing sample is irradiated with the laser instrument 30 of Raman system, laser instrument 30 sends laser excitation and collects testing sample Raman spectrum at different temperatures, obtains first spectral value of testing sample under different temperatures value.

The wavelength of laser is 240nm ~ 800nm, is preferably 633nm.

Wherein, the step-length of multiple temperature value preferably 10 DEG C, namely multiple temperature value is arithmetic progression, and tolerance is 10 DEG C.The step-length selecting temperature value is 10 DEG C, makes the accuracy of linear relationship higher.

Preferably, testing sample is heated above the temperature of the glass transition temperature 60 DEG C of polymkeric substance from 22 DEG C, with 10 DEG C for step-length.Such as, when the glass transition temperature of polymkeric substance is 102 DEG C, sample is heated to 162 DEG C from 22 DEG C, with 10 DEG C for the Raman spectrum under step-length mensuration different temperatures value, namely measure 15 Raman spectrums of testing sample at 22 DEG C, 32 DEG C, 42 DEG C, 52 DEG C, 62 DEG C, 72 DEG C, 82 DEG C, 92 DEG C, 102 DEG C, 112 DEG C, 122 DEG C, 132 DEG C, 142 DEG C, 152 DEG C and 162 DEG C respectively and obtain 15 the first spectral values.

This polymkeric substance is subsequent measurements polymkeric substance used.

Preferably, for ensureing the step-length of 10 DEG C, when the value of glass temperature+60 DEG C and the difference of penultimate temperature value are not 10 DEG C, testing sample is heated above near glass transition temperature 60 DEG C as test terminal temperature.

Take temperature value as horizontal ordinate, with the first spectral value for ordinate, by multiple temperature value and accordingly multiple first spectral value carry out linear fit, obtain the temperature of testing sample and the linear relationship of Raman spectrum, according to this linear relationship, that determines testing sample changes by unit temperature the Raman peaks amount of movement caused, and counts χ _f.

Step S120: testing sample and polymkeric substance are carried out being mixed to get potpourri, potpourri ultrasonic disperse is obtained compound substance.

Preferably, by testing sample and polymkeric substance in mass ratio 1:50 ~ 1:5000 carry out being mixed to get potpourri.Select this mass ratio that testing sample can be made to be well-dispersed in polymkeric substance, and polymkeric substance can not produce interference to measurement result.

More preferably, the mass ratio of testing sample and polymkeric substance is 1:724.

Potpourri is carried out ultrasonic disperse, with make testing sample evenly, be well-dispersed in polymkeric substance, obtain compound substance.

Preferably, by potpourri ultrasonic disperse 15 hours, disperse equably with polymkeric substance to make testing sample.

Polymkeric substance is preferably epoxy resin, phenolics, polystyrene, PPTA, polyethylene terephthalate, polybenzimidazoles, polyetheretherketone or polyimide.

Need for measuring, in other embodiments, this compound substance also comprises hardening agent, so that can curing molding.

Step S130: different deformation is applied to compound substance, multiple surface strain values of compound substance are measured with device for measurement of strain, and the spectrum of testing sample under different surface strain values measured in compound substance obtains multiple second spectral value, multiple surface strain values and multiple second spectral value are carried out linear fit, determine that the unit strain of testing sample causes, being parallel to should nyctitropic spectrum peak amount of movement, counts S ₀.

Be cut into strip by after polymer cure, obtain long × wide × high strip resin being preferably 70mm × 10mm × 3mm.Compound substance is coated on the surface of strip resin before solidification, after solidification, on the surface of strip resin, forms coating.The sides aligned parallel of coating and strip resin.

The thickness of coating is preferably 20 microns.

Stick foil gauge at coating edge, two electrodes of foil gauge are drawn with electric wire and are electrically connected with device for measurement of strain, to be determined at the strain that strip resin applies.

Preferably, strain is applied with four-point bending device.

Preferably, device for measurement of strain is oscillograph.

Preferably, scope strip resin being applied to strain is 0 ~ 0.4%, and step-length is 0.04%.Namely start to be 0 to the strain that strip resin applies, be then increased to 0.04%, 0.08%, 0.12%, 0.16%, 0.20%, 0.24%, 0.28%, 0.32%, 0.36% and 0.40% successively.

Measure multiple Raman spectrums that strain is 0,0.04%, 0.08%, 0.12%, 0.16%, 0.20%, 0.24%, 0.28%, 0.32%, 0.36% and 0.40% correspondence respectively, obtain the second spectral value.Be appreciated that in other embodiments, the second spectral value also can be fluorescence emission spectrum value or infrared light spectrum.

Take surface strain values as horizontal ordinate, with the second spectral value for ordinate, 11 strain values and corresponding 11 the second spectral values carried out linear fit, determine that the unit strain of testing sample causes, being parallel to should nyctitropic Raman peaks amount of movement, counts S ₀.

Step S140: the spectrum of testing sample under different temperatures value measured in compound substance obtains multiple 3rd spectral value, different temperatures value and multiple 3rd spectral value are carried out linear fit, determine the testing sample in compound substance by unit temperature change cause spectrum peak amount of movement, count χ _c.

Warm table 10 is positioned on objective table 20, and compound substance is placed on warm table 10 and heats, testing sample is irradiated with the laser instrument 30 of Raman system, laser instrument 30 sends the testing sample spectrum at different temperatures in laser excitation collection compound substance, obtains three spectral value of testing sample under different temperatures value in compound substance.

Measuring above-mentioned compound substance is measure with the form of coating.Coating the compound substance formation coating of hardening agent can be comprised on the carrier being convenient to stripping.The thickness of coating is preferably 20 microns.Carrier can tinfoil paper, aluminium foil, glass etc.

Wherein, the step-length of multiple temperature value preferably 10 DEG C, namely multiple temperature value is arithmetic progression, and tolerance is 10 DEG C.

The wavelength of laser is 240nm ~ 800nm, is preferably 633nm.

Wherein, the step-length of multiple temperature value preferably 10 DEG C, namely multiple temperature value is arithmetic progression, and tolerance is 10 DEG C.The step-length selecting temperature value is 10 DEG C, makes the accuracy of linear relationship higher.

Preferably, compound substance is heated above the temperature of the glass transition temperature 60 DEG C of polymkeric substance from 22 DEG C, with 10 DEG C for step-length.

Preferably, for ensureing the step-length of 10 DEG C, when the value of the glass temperature+60 DEG C of polymkeric substance and the difference of penultimate temperature value are not 10 DEG C, as test terminal temperature near value compound substance being heated to the glass transition temperature+60 DEG C of polymkeric substance.

Take temperature value as horizontal ordinate, with the 3rd spectral value for ordinate, multiple temperature value and multiple corresponding 3rd spectral value are carried out linear fit, obtain the temperature of the testing sample in compound substance and the linear relationship of Raman spectrum, according to this linear relationship, that determines the testing sample in compound substance to be measured changes by unit temperature the Raman peaks amount of movement caused, and counts χ _c.

Be appreciated that in other embodiments, the 3rd spectral value also can be fluorescence emission spectrum value or infrared light spectrum.

Step S150: according to α _f=α _e-(χ _c-χ _f)/S ₀calculate the thermal expansivity of testing sample.

χ is obtained by above-mentioned steps _f, S ₀and χ _cafter, by above-mentioned formula (7): α _f=α _e-(χ _c-χ _f)/S ₀calculate, namely obtain the thermalexpansioncoefficientα of testing sample _f.

Wherein, α _efor the thermal expansivity of polymkeric substance, its value is known or obtained by mensuration.

Raman spectrum is the spectral technique of a kind of detection molecules vibration, and it measures, and sample preparation is simple, fast, the sample morphology be suitable for is extensive, is a kind of easy, efficient detection means.Raman G ' peak the frequency of carbon nanomaterial and its strain linear, tensile force makes its Raman peaks move to low frequency, and force of compression makes it shift to high frequency.G ' peak frequency and temperature also linear, heat up its Raman peaks is moved to low frequency, and cooling make it shift to high frequency.Therefore can by in-situ Raman spectrum the temperature of carbon nanomaterial be associated with strain thus determine its thermal expansivity.

Utilize the detection means of fluorescence emission spectrum and infrared spectrum also to have easy, efficient advantage, the thermal expansivity of testing sample can be measured comparatively quickly and accurately.

The assay method of above-mentioned thermal expansivity is the thermal expansivity based on Raman spectrum, fluorescence emission spectrum or infrared spectrometry testing sample.Measure the Raman spectrum of the testing sample in the Raman spectrum of testing sample, fluorescence emission spectrum or infrared spectrum variation with temperature, polymeric matrix, fluorescence emission spectrum or infrared spectrum by Raman system, fluorescent emission system or infrared system and vary with temperature three parameters with temperature with the Raman spectrum of the testing sample in the change of strain and polymeric matrix, fluorescence emission spectrum or infrared spectrum, the thermal expansivity of testing sample can be calculated.The assay method of this thermal expansivity is simple, and it is convenient to measure, and can measure the thermal expansivity of testing sample comparatively quickly and accurately.

Use the assay method of above-mentioned thermal expansivity can not only the thermal expansivity of Measurement accuracy carbon nanomaterial, to solve science and the industry member difficult problem of the thermal expansivity measuring at present carbon nanomaterial, can also be used for measuring polymkeric substance, high-strength structure material, thermal interfacial material, multiple field such as mensuration for insulating material in the silicon through hole of electric interconnection.

Preferably, the α of polymkeric substance _emeasure as follows.

Step S210: measure the spectral value that the spectrum of fibrous material under different temperatures value obtains multiple fibrous material respectively, the spectral value of different temperatures value and multiple fibrous material is carried out linear fit, that determines fibrous material changes by unit temperature the spectrum peak amount of movement caused, and counts χ _f1.

Fibrous material selects the fibrous material of heat resistance more than 120 DEG C, is preferably the fibrous materials such as alumina fibre, carbon fiber or aramid fiber.

Fibrous material as internal standard compound, its thermalexpansioncoefficientα _f1for known.The spectral value of fibrous material can be Raman spectrum value, fluorescence emission spectrum or infrared light spectrum.

For Raman light spectrum, warm table 10 is positioned on objective table 20, and fibrous material is placed on warm table 10 and heats, testing sample is irradiated with the laser instrument 30 of Raman system, laser instrument 30 sends laser excitation and collects fibrous material Raman spectrum at different temperatures, obtain the spectral value of fibrous material under different temperatures value, obtain the spectral value of multiple fibrous material.

The wavelength of laser is 240nm ~ 800nm, is preferably 633nm.

Fibrous material is heated above the temperature of the glass transition temperature 60 DEG C of polymkeric substance from 22 DEG C, measures the Raman spectrum at multiple temperature.Wherein, the step-length of multiple temperature value preferably 10 DEG C, namely multiple temperature value is arithmetic progression, and tolerance is 10 DEG C.Preferably, for ensureing the step-length of 10 DEG C, when the value of glass temperature+60 DEG C and the difference of penultimate temperature value are not 10 DEG C, as test terminal temperature near value fibrous material being heated to its glass transition temperature+60 DEG C.

Take temperature value as horizontal ordinate, with the spectral value of fibrous material for ordinate, the spectral value of multiple temperature value and multiple corresponding fibrous material is carried out linear fit, obtain the temperature of fibrous material and the linear relationship of Raman spectrum, according to this linear relationship, that determines fibrous material changes by unit temperature the Raman peaks amount of movement caused, and counts χ _f1.

Step S220: will cut into strip resin after polymer cure, be positioned over by fibrous material on strip resin, and separately take polymkeric substance, is coated on fibrous material by the polymkeric substance separately taken, obtains compound after solidification before solidification.

The step obtaining compound is specially: take a certain amount of polymkeric substance, is cut into strip resin by after this polymer cure.Fibrous material is lain on strip resin, make it be parallel to strip resin edge, then, separately take a certain amount of polymkeric substance, the polymkeric substance this separately taken is coated on the surface of fibrous material before solidification, forms coating, obtain compound after solidification on the surface of fibrous material.

Length × wide × high preferably 70mm × 10mm × 3mm of strip resin.The thickness of coating is preferably 20 microns.

Step S230: different deformation is applied to compound, multiple surface strain values of compound are measured with device for measurement of strain, and the multiple spectral values of the fibrous material measured in compound under different surface strain values obtain the first spectral value of the fibrous material in multiple compound, the first spectral value in fibrous material in multiple surface strain values and multiple compound is carried out linear fit, determine fibrous material caused by unit strain, being parallel to should nyctitropic spectrum peak amount of movement, counts S ₀₁.

Stick foil gauge at the edge of coating, two electrodes of foil gauge are drawn with electric wire and are electrically connected with device for measurement of strain, to be determined at the strain that strip resin applies.

Preferably, strain is applied with four-point bending device.Device for measurement of strain is oscillograph.

Preferably, scope strip resin being applied to strain is 0 ~ 0.4%, and step-length is 0.04%.Namely start to be 0 to the strain that strip resin and coating apply, be then increased to 0.04%, 0.08%, 0.12%, 0.16%, 0.20%, 0.24%, 0.28%, 0.32%, 0.36% and 0.40% successively.

Measure multiple Raman spectrums that strain is 0,0.04%, 0.08%, 0.12%, 0.16%, 0.20%, 0.24%, 0.28%, 0.32%, 0.36% and 0.40% correspondence respectively, obtain the second Raman light spectrum.

Take surface strain values as horizontal ordinate, with the first spectral value of the fibrous material in compound for ordinate, first spectral value of the fibrous material in 11 strain values and corresponding compound is carried out linear fit, determine fibrous material caused by unit strain, being parallel to should nyctitropic Raman peaks amount of movement, counts S ₀₁.

Be appreciated that in other embodiments, the first spectral value of the fibrous material in compound can be fluorescence emission spectrum or infrared spectrum.

Step S240: the spectrum of fibrous material under different temperatures value measured in compound obtains the second spectral value of the fibrous material in multiple compound, second spectral value of the fibrous material in different temperatures value and multiple compound is carried out linear fit, that determines the fibrous material in compound to be measured changes by unit temperature the spectrum peak amount of movement caused, and counts χ _c1.

The wavelength of laser is 240nm ~ 800nm, is preferably 633nm.

For the second spectral value of the fibrous material in compound, compound is heated above the temperature of glass transition temperature of polymer 60 DEG C from 22 DEG C, measures the Raman spectrum at multiple temperature.Wherein, the step-length of multiple temperature value preferably 10 DEG C, namely multiple temperature value is arithmetic progression, and tolerance is 10 DEG C.The step-length selecting temperature value is 10 DEG C, makes the accuracy of linear relationship higher.

Preferably, compound is heated above the temperature of the glass transition temperature 60 DEG C of polymkeric substance from 22 DEG C, with 10 DEG C for step-length.

Preferably, for ensureing the step-length of 10 DEG C, when the value of glass temperature+60 DEG C and the difference of penultimate temperature value are not 10 DEG C, as test terminal temperature near temperature compound being heated to the glass transition temperature+60 DEG C of polymkeric substance.

Take temperature value as horizontal ordinate, with the second spectral value of the fibrous material in compound for ordinate, second spectral value of the fibrous material in multiple temperature value and multiple corresponding compound is carried out linear fit, obtain the temperature of the fibrous material in compound and the linear relationship of Raman spectrum, according to this linear relationship, that determines the fibrous material in compound changes by unit temperature the Raman peaks amount of movement caused, and counts χ _c1.

Be appreciated that in other embodiments, the second spectral value of the fibrous material in compound can be fluorescence emission spectrum or infrared spectrum.

Step S250: according to α _e1=α _f1+ (χ _c1-χ _f1)/S ₀₁calculate the thermal expansivity of polymkeric substance.

χ is obtained by above-mentioned steps _f1, S ₀₁and χ _c1after, by formula: α _e1=α _f1+ (χ _c1-χ _f1)/S ₀₁calculate, namely obtain the thermalexpansioncoefficientα of polymkeric substance _e1.

Wherein, α _e1for the thermal expansivity of polymkeric substance.α _f1for the thermal expansivity of fibrous material, its value is known.

Said method can measure the thermalexpansioncoefficientα of polymkeric substance exactly _e1, the thermalexpansioncoefficientα of polymkeric substance is measured by said method _e1after, then adopt the step of above-mentioned steps S110 ~ S140 to measure, by α _e1as α _ebring in above-mentioned formula (7), measure the thermalexpansioncoefficientα obtaining the testing samples such as carbon nanomaterial _f.The method being measured the thermal expansivity of polymkeric substance by employing fibrous material as internal standard compound further increases the accuracy of the MEASURING THE THERMAL EXPANSION COEFFICIENT of the other materials such as carbon nanomaterial.

Set forth further below by way of specific embodiment.

Embodiment 1

Measure the thermal expansivity of bisphenol A type epoxy resin

1, single alumina fibre is placed in warm table, warm table is placed on optical microscope stage, alumina fibre is heated, for step-length heating between 22 DEG C to 142 DEG C, with 10 DEG C, Raman spectrum under adopting Renishaw2000 Raman system to measure different temperatures, collect alumina fibre Raman spectrum at different temperatures with 633nm laser excitation, obtain 13 the first Raman light spectrum.Wherein, the R1 peak of alumina fibre under 295K and 415K as shown in Figure 3.Using 22 DEG C, 32 DEG C, 42 DEG C, 52 DEG C, 62 DEG C, 72 DEG C, 82 DEG C, 92 DEG C, 102 DEG C, 112 DEG C, 122 DEG C, 132 DEG C and 142 DEG C of these 13 temperature values as horizontal ordinate, using corresponding 13 the first Raman light spectrum as ordinate, 13 temperature values and 13 corresponding first Raman light spectrum are carried out linear fit, as shown in Figure 4, linear relationship is ω to linear graph _r1=1354+0.154T.χ is determined according to this linear relationship _f1, numerical value lists in table 1;

2, by bisphenol A type epoxy resin and hardening agent in mass ratio 100:38 carry out the potpourri being mixed to get bisphenol A type epoxy resin and hardening agent, the potpourri of a part of bisphenol A type epoxy resin and hardening agent is at room temperature solidified 24 hours, then solidify 4 hours at 100 DEG C, after solidification, be cut into the strip resin of 70mm × 10mm × 3mm.Single alumina fibre is lain on strip resin, it is made to be parallel to strip resin edge, the potpourri of another part bisphenol A type epoxy resin and hardening agent is coated on alumina fibre before solidifying, cured at room temperature 24 hours, then solidification 4 hours at 100 DEG C, forms the coating be coated on alumina fibre surface, obtains compound to be measured, wherein, the thickness of coating is 20 microns;

3, paste foil gauge at the 3mm place, side of strip resin and alumina fibre, foil gauge two electrode is drawn with wire.Compound to be measured is inserted four-point bending device, places it on optical microscope stage, deformation is applied to strip resin and coating, answers variable step to be 0.04%, by oscilloscope measurement surface strain.Adopt Renishaw2000 Raman system, collect alumina fibre at differently strained lower Raman spectrum with 633nm laser excitation, obtain multiple second Raman light spectrum.The R1 peak of compound to be measured and strain stress relation be (0% strains and the 0.4% peak figure strained) as shown in Figure 5.To strain 0%, 0.04%, 0.08%, 0.12%, 0.16%, 0.20%, 0.24%, 0.28%, 0.32%, 0.36% and 0.40% as horizontal ordinate, with multiple second Raman light spectrum of correspondence for ordinate carries out linear fit, as shown in Figure 6, linear relationship is ω to linear graph _r1=1405-12 × 10 ^-2ε.S is determined according to this linear relationship ₀₁, numerical value lists in table 1.

4, compound to be measured is placed in warm table, for step-length heating between 22 DEG C to 152 DEG C, with 10 DEG C, adopts Renishaw2000 Raman system, collect fiber fluorescent emission spectrum at different temperatures with 633nm laser excitation, obtain multiple 3rd Raman light spectrum.The R1 peak of sample varies with temperature relation as shown in Figure 7.There is glass transition at about 102 DEG C and enter elastomeric state in bisphenol A type epoxy resin, the Stress transmit efficiency from resin to alumina fibre reduces, and is therefore determining χ _ctime the data point only chosen between 22 DEG C ~ 102 DEG C make linear fit.Respectively using 22 DEG C, 32 DEG C, 42 DEG C, 52 DEG C, 62 DEG C, 72 DEG C, 82 DEG C, 92 DEG C and 102 DEG C as horizontal ordinate, using relative multiple 3rd Raman light spectrum as ordinate, carry out linear fit, linear relationship chart as shown in Figure 8.Linear relationship is ω _r1=1381+0.079T, determines χ according to this linear relationship _c1, numerical value lists in table 1.

The thermal expansivity of alumina fibre is 9 × 10 ^-6k ^-1, i.e. α _f1=9 × 10 ^-6k ^-1.By α _f1and the χ that said determination obtains _f1, S ₀₁and χ _c1substitute into formula α _e1=α _f1+ (χ _c1-χ _f1)/S ₀₁in, calculate the thermalexpansioncoefficientα of bisphenol A type epoxy resin _e1, numerical value lists in table 1.

The data that the thermal expansivity of the bisphenol A type epoxy resin recorded by said method and Huntsman Products technical manual provide are coincide, and illustrate that the assay method of the above-mentioned thermal expansivity based on Raman spectrum is very reliable.

Embodiment 2

Measure the thermal expansivity of carbon nano-tube

1, Single Walled Carbon Nanotube is placed in warm table, warm table is placed on optical microscope stage, carbon nano-tube is heated, for step-length heating between 22 DEG C to 162 DEG C, with 10 DEG C, adopt Renishaw2000 Raman system, collect carbon nano-tube Raman spectrum at different temperatures with 633nm laser excitation, obtain 15 the first spectral values.Using 22 DEG C, 32 DEG C, 42 DEG C, 52 DEG C, 62 DEG C, 72 DEG C, 82 DEG C, 92 DEG C, 102 DEG C, 112 DEG C, 122 DEG C, 132 DEG C, 142 DEG C, 152 DEG C and 162 DEG C of these 15 temperature values as horizontal ordinate, using corresponding 15 the first spectral values as ordinate, 15 temperature values and 15 corresponding first spectral values are carried out linear fit, as shown in Figure 9, linear relationship is ω to linear graph _{g '}=2643-0.029T.χ is determined according to this linear relationship _f, numerical value lists in table 1;

2, join in 7.24g bisphenol A type epoxy resin by 10mg Single Walled Carbon Nanotube, ultrasonic disperse 15 hours, obtains the potpourri of resin and carbon nano-tube.2.76g hardening agent is added to this potpourri, mix and obtain compound substance, this compound substance is coated in the strip resin of 70mm × 10mm × 3mm before solidification, and (bisphenol A type epoxy resin and hardening agent in mass ratio 100:38 mix, after solidification, cutting obtains, preparation method is with embodiment 1) on, on the surface of strip resin, form coating after solidification, coating thickness is 20 microns.The method of solidification at room temperature solidifies 24 hours, then solidification 4 hours at 100 DEG C;

3, paste foil gauge at the 3mm place, side of coating, the electrode of foil gauge is drawn with wire.Compound substance to be measured is inserted self-control four-point bending device and is placed on optical microscope stage, deformation is applied to strip resin and coating.By oscilloscope measurement surface strain.Adopt Renishaw2000 Raman system, the Raman spectrum of Single Walled Carbon Nanotube under different surfaces strain is collected with 633nm laser excitation, obtain multiple second spectral value, using surface strain 0%, 0.04%, 0.08%, 0.12%, 0.16%, 0.20%, 0.24%, 0.28%, 0.32%, 0.36% and 0.40% as horizontal ordinate, with multiple second spectral values of correspondence for ordinate carries out linear fit, linear graph as shown in Figure 10.Linear relationship is ω _{g '}=2635-14.6 ε.S is determined according to this linear relationship ₀, namely by ω _{g '}=2635-14.6 × 10 ^-2ε determines S (0)=14.6, S ₀=1.3 × S (0), numerical value lists in table 1;

4, painting is placed in warm table, for step-length heating between 22 DEG C to 162 DEG C, with 10 DEG C, adopt Renishaw2000 Raman system, compound substance to be measured Raman spectrum is at different temperatures collected with 633nm laser excitation, respectively using 22 DEG C, 32 DEG C, 42 DEG C, 52 DEG C, 62 DEG C, 72 DEG C, 82 DEG C, 92 DEG C and 102 DEG C as horizontal ordinate, so that multiple 3rd spectral value is as ordinate accordingly, carry out linear fit, linear relationship chart as shown in figure 11.Linear relationship is ω _{g '}=2674-0.129T, determines χ according to this linear relationship _c, numerical value lists in table 1.

The thermal expansivity of Single Walled Carbon Nanotube can by formula α _f=α _e-(χ _c-χ _f)/S ₀determine, wherein, α _efor the thermal expansivity of bisphenol A type epoxy resin, be 7.2 × 10 ^-5k ^-1, measured by embodiment 1 and obtain, calculate the thermalexpansioncoefficientα of Single Walled Carbon Nanotube _flist in table 1.

Table 1

The above embodiment only have expressed several embodiment of the present invention, and it describes comparatively concrete and detailed, but therefore can not be interpreted as the restriction to the scope of the claims of the present invention.It should be pointed out that for the person of ordinary skill of the art, without departing from the inventive concept of the premise, can also make some distortion and improvement, these all belong to protection scope of the present invention.Therefore, the protection domain of patent of the present invention should be as the criterion with claims.

Claims (10)

1. an assay method for thermal expansivity, comprises the steps:

Measure the spectrum of testing sample under different temperatures value respectively and obtain multiple first spectral value, described different temperatures value and described multiple first spectral value are carried out linear fit, that determines described testing sample changes by unit temperature the spectrum peak amount of movement caused, and counts χ _f;

Described testing sample and polymkeric substance are carried out being mixed to get potpourri, described potpourri ultrasonic disperse is obtained compound substance;

Different deformation is applied to described compound substance, multiple surface strain values of described compound substance are measured with device for measurement of strain, and the spectrum of testing sample under different surface strain values measured in described compound substance obtains multiple second spectral value, described multiple surface strain values and described multiple second spectral value are carried out linear fit, determine described testing sample caused by unit strain, being parallel to should nyctitropic spectrum peak amount of movement, counts S ₀;

The spectrum of testing sample under different temperatures value measured in described compound substance obtains multiple 3rd spectral value, described different temperatures value and described multiple 3rd spectral value are carried out linear fit, that determines the testing sample in described compound substance changes by unit temperature the spectrum peak amount of movement caused, and counts χ _c; And

The thermal expansivity of described testing sample is obtained according to following formulae discovery:

α _F=α _E-(χ _C-χ _F)/S ₀；

Wherein, described α _frepresent the thermal expansivity of described testing sample, described α _efor the thermal expansivity of described polymkeric substance;

Described first spectral value, the second spectral value and the 3rd spectral value are Raman light spectrum, fluorescence emission spectrum or infrared light spectrum.

2. the assay method of thermal expansivity according to claim 1, it is characterized in that, describedly measure the step that the spectrum of testing sample under different temperatures value obtains multiple first spectral value respectively and be specially: be 10 DEG C with step-length, measure described testing sample respectively and obtain multiple first spectral value to the multiple spectrum under multiple temperature values of the temperature of the glass transition temperature 60 DEG C higher than described polymkeric substance from 22 DEG C.

3. the assay method of thermal expansivity according to claim 1, it is characterized in that, described polymkeric substance is epoxy resin, phenolics, polystyrene, PPTA, polyethylene terephthalate, polybenzimidazoles, polyetheretherketone or polyimide.

4. the assay method of the thermal expansivity according to claim 1 or 3, is characterized in that, in described potpourri, the mass ratio of described testing sample and polymkeric substance is 1:50 ~ 1:5000.

5. the assay method of thermal expansivity according to claim 1, is characterized in that, is 0.5 hour ~ 24 hours by the time of described potpourri ultrasonic disperse.

6. the assay method of thermal expansivity according to claim 1, it is characterized in that, described different deformation is applied to described compound substance, the step measuring multiple surface strain values of described compound substance with device for measurement of strain is specially: cut into strip resin by after described polymer cure, and described compound substance is coated on before solidification the surface of described strip resin, coating is formed on the surface of described strip resin after described composite material solidification, foil gauge is sticked at the edge of described coating, described foil gauge is electrically connected with described device for measurement of strain, different deformation is applied to described strip resin.

7. the assay method of thermal expansivity according to claim 6, is characterized in that, the scope described strip resin being applied to deformation is 0 ~ 0.4%, and step-length is 0.04%.

8. the assay method of thermal expansivity according to claim 1, it is characterized in that, the step that the spectrum of testing sample under different temperatures value in the described compound substance of described mensuration obtains multiple 3rd spectral value is specially: be 10 DEG C with step-length, measures testing sample in described compound substance respectively and obtain multiple 3rd spectral value to the multiple spectrum under multiple temperature values of the temperature of the glass transition temperature 60 DEG C higher than described polymkeric substance from 22 DEG C.

9. the assay method of thermal expansivity according to claim 1, is characterized in that, the thermalexpansioncoefficientα of described polymkeric substance _emeasure as follows:

Measure the spectral value that the spectrum of fibrous material under different temperatures value obtains multiple fibrous material respectively, the spectral value of described different temperatures value and described multiple fibrous material is carried out linear fit, that determines described fibrous material changes by unit temperature the spectrum peak amount of movement caused, and counts χ _f1;

Cut into strip resin by after described polymer cure, described fibrous material is positioned on described strip resin, and separately takes described polymkeric substance, the described polymkeric substance separately taken is coated on described fibrous material before solidification, after solidification, obtains compound;

Different deformation is applied to described compound, the multiple surface strain values of described compound is measured with device for measurement of strain, and the multiple spectral values of the fibrous material measured in described compound under different surface strain values obtain the first spectral value of the fibrous material in multiple compound, first spectral value of the fibrous material in described multiple surface strain values and described multiple compound is carried out linear fit, determine that the unit strain of described fibrous material causes, being parallel to should nyctitropic spectrum peak amount of movement, counts S ₀₁;

The spectrum of fibrous material under different temperatures value measured in described compound obtains the second spectral value of the fibrous material in multiple compound, second spectral value of the fibrous material in described different temperatures value and described multiple compound is carried out linear fit, that determines the fibrous material in described compound changes by unit temperature the spectrum peak amount of movement caused, and counts χ _c1; And

The thermal expansivity of described polymkeric substance is calculated according to following formula:

α _E1=α _F1+(χ _C1-χ _F1)/S ₀₁；

Wherein, described α _e1represent the thermal expansivity of described polymkeric substance, described α _f1for the thermal expansivity of described fibrous material;

Second spectral value of the fibrous material in the first spectral value of the fibrous material in the spectral value of described multiple fibrous material, multiple compound and multiple compound is Raman light spectrum, fluorescence emission spectrum or infrared light spectrum.

10. the assay method of thermal expansivity according to claim 9, is characterized in that, described fibrous material is alumina fibre, carbon fiber or aramid fiber.