CN1152245C - Fast test method of ethylene-propylene rubber content in ethylene-propylene copolymer - Google Patents

Abstract

The present invention relates to a rapid determination method of ethylene-propylene rubber content in ethylene-propylene copolymerized polypropylene. In the method, the weight percentage of ethylene-propylene copolymerized polypropylene and the absorbance values of the five absorption peaks of 810cm<-1>, 752cm<-1>, 735cm<-1>, 730cm<-1> and 720cm<-1> are determined by a Fourier transform infrared spectroscopy, according to the formula of R=C2<2>m%*(1-A720/sigma), the value of R is calculated, the R value has a linear relationship with the ethylene-propylene rubber content in the ethylene-propylene copolymerized polypropylene, and thus, the ethylene-propylene rubber content in the ethylene-propylene copolymerized polypropylene can be calculated.

Description

The method of the second third glue content in the fast measuring ethylene, propylene COPP

One, technical field

The present invention relates to the content of second third glue in the infrared spectrum measurement ethylene, propylene COPP.

Two, background technology

Ethene and propylene Ziegler one Natta catalyst copolymerization suitability for industrialized production product based on propylene also claim " second third COPP " that its many character particularly impact strength are significantly increased than isotactic polypropylene, and the domestic and international market is very good.

The final purpose of second third copolymerization is to introduce EP rubbers (EPR), and its content directly influences the quality of second third COPP.This is because of the EP rubbers of introducing in polypropylene (EPR), has improved the shock resistance of product well.Therefore, one of key parameter that content simple and direct, that measure second third glue (EPR) in second third COPP quickly and accurately is technology controlling and process during COPP is produced, requisite internal control index in the product inspection also is that the good COPP of industrialized production device long-period stable operation and production is necessary.

The method of second third glue (EPR) assay only has traditional chemical extraction method in second third COPP.This method is time-consuming, and each sample analysis reaches 6-7 hour.Error is big, in extraction process such as extraction, filter, very easily produce error in dry, the too many levels such as weigh.Simultaneously, n-decane that in extraction, uses or dimethylbenzene, the acetone equal solvent is contaminated environment very easily, and analysis cost is also high.The high-impact second third COPP production difficulty is bigger, requires the analytical test means faster, and accurately, and extraction can not satisfy this requirement.

Three, summary of the invention

The method that the purpose of this invention is to provide the second third glue content in a kind of quick, pollution-free, mensuration ethylene, propylene COPP that error is less.

Technical scheme of the present invention is as follows:

The method of the second third glue content is the method for the second third glue content in a kind of infrared spectrum fast measuring ethylene, propylene COPP in the fast measuring ethylene, propylene COPP of the present invention, and it is made up of following steps:

(1) measures the FT-IR infrared spectrogram of ethylene, propylene COPP with the Fourier Tranform infrared spectrometer.

(2) measure the content mass percent C of ethene in the ethylene, propylene COPP ₂ ^=m% (its method is " ethylene contents rapid test method in the ethylene, propylene COPP " patented claim of 00112047.6 referring to number of patent application).

(3) from infrared spectrogram, measure the second third glue characteristic peak group 810cm ^-1, 752cm ^-1, 735cm ^-1, 730cm ^-1, 720cm ^-1The absorbance A of five absorption peaks ₈₁₀, A ₇₅₂, A ₇₃₅, A ₇₃₀, A ₇₂₀.

(4) R=C by formula ₂M% * (1-) calculates R value, wherein C ₂M% is the content mass percent of ethene in the ethylene, propylene COPP, and A is A ₈₁₀+ A ₇₅₂+ A ₇₃₅+ A ₇₃₀+ A ₇₂₀Sum.

(5) obtain formula with at least three standard models by regression analysis

The value of A and B among the Y%=AR+B, or make typical curve, wherein Y% is the content mass percent of second third glue in the ethylene, propylene COPP.

(6) testing sample is measured the R value by above-mentioned (1) to (4) step, from typical curve, obtain the Y% value, or calculate the Y% value with formula Y%=AR+B.

Method of the present invention can be measured the percentage composition of second third glue in the ethylene, propylene COPP quick, easy, more exactly with the Fourier Tranform infrared spectrometer, the content of ethylene, propylene COPP and the content of second third glue in an infrared spectrum measurement, both can have been measured, wherein the measurement absolute error of second third glue is smaller or equal to 1%, relative error≤15%.Can provide process control parameter in the production for producing high-quality ethylene, propylene COPP preferably, and the quality inspection index of the poly-Class C product of ethylene, propylene copolymerization.

Four, description of drawings

Fig. 1 is an ethylene, propylene COPP FT-IR infrared spectrogram;

Fig. 2 is the FT-IR infrared spectrogram of the characteristic peak group of EPR assay.

Five, embodiment

Further specify method of the present invention by the following examples.

The third COPP standard specimen EPR content regretional analysis of embodiment 1 second

The EPR content value (being set at actual value) that provides chemical extraction method to measure each second third COPP standard specimen according to the Mitsui oiling, and with this standard that edits as the infrared spectrum quantitative analysis.

1.1 testing tool

This method is suitable for various model FT-IR Fourier transform infrared spectrometer.

Instrument of the present invention:

(1) FT-IR1760 of U.S. PE company type, the Fourier Tranform infrared spectrometer,

Energy of light source:＞30000

Resolution: 4.0cm ^-1

Scanning times: 20 times

(2) U.S. PE company, the SPECAC molding press

Pressure: 0-15t (making service pressure is 4t)

Temperature: 0-300 ℃ (temperature is 180 ± 1 ℃ during use)

1.2 test condition:

Test environment temperature: 25 ± 3 ℃

Test environment humidity: RH≤60%

1.3 specimen is made:

(1) the sample pellet is placed metal die put on 180 ± 1 ℃ of warm tables, fusion was forced into 4t until 180 ℃ in 3 minutes, and constant temperature takes out after 5 minutes and puts in the cooling box (water-cooled), is cooled to room temperature, and it is to be measured to take out matrix.

(2) film matrix thickness 220-250 μ m selects the supporting press box of SPECAC molding press " E " frame for use.

(3) powder is operated with pellet, no specific (special) requirements.

1.4 testing procedure

(1) whether temperature, the humidity of checkout environment meets the requirements before the test, operate under the temperature of stipulating, humidity.

(2) FT-IR infrared spectrometer start, stablize whether inspection apparatus resolution, energy, signal to noise ratio (S/N ratio) reach the given index of producer after 30 minutes, carry out 0% then, 100% transmitance and background noise scanning, enter (if the start everyday of next step test operation after normal, this step all can regularly be carried out except that background scans the same is done).

(3) second third COPP is suppressed the identical diaphragm of thickness by the film-making requirement, two parallel testings of every sample system are used.Diaphragm thickness differs≤5 μ m, otherwise compacting again, to conforming with thickness requirement.

(4) FT-IR infrared spectrometer wave-number range is set 4500-450cm ^-1Carry out background scans (being convenient to carry out simultaneously ethylene contents measures).

(5) again the print that suppresses is inserted mensuration transmissivity infrared spectrogram on the support of FT-IR sample chamber, test back deposit machine calculation process to be calculated.

1.5 test result, calculating

(1) with the machine processing as calculated of the gained second third COPP transmitted infrared light spectrogram, converts the absorbance infrared spectrogram to.

(2) on FT-IR absorbance infrared spectrogram, utilize computing machine to amplify 900cm ^-1-600cm ^-1Local spectrum calculates the absorbance (referring to Fig. 2) at each peak of EPR characteristic peak group.

(3) the R value (seeing Table R value calculation procedure in 1) of calculating EPR characteristic peak group.

(4) Y in the according to standard sample _EPRThe % value calculates A, B value or makes working curve.

1.6 the technical standard of this method

This method accuracy represents that with absolute error, relative error the relevant of Error Calculation is described as follows:

(1) be actual value (u) with second third glue (EPR) content in measured second third COPP of chemical extraction method.

(2) record with FT-IR that the second third glue content value is measured value of experiment (Y) in second third COPP.

1.7 absolute error: measured value and actual value poor

(1) formulate:

Absolute error (±)=measured value-actual value=Y-u

Positive and negative number expression analysis result ,+: more higher than actual value

-: more on the low side than actual value

(2) this method bounded absolute error :≤1%.

1.8 relative error: the ratio of absolute error and actual value

(1) formulate:

(2) this method relative error scope :≤15%.

The regretional analysis of table 1.EPR content

Embodiment 2 sample YZ601 ^#The third glue content express-analysis of the second third COPP second

Chemical extraction method is measured sample YZ601 ^#EPR actual value u=7.7%

(1) the different print FT-IR of same sample measured value the results are shown in Table 2.

The different print EPR of the same sample of table 2 measured value

Print	FT-IR surveys the R value	FT-IR surveys Y value (EPR%)	Absolute error
				1	8.3937	8.2	0.5
2	8.4515	8.2	0.5
				3	8.3696	8.2	0.5
4	8.4263	8.2	0.5
				5	8.2719	8.1	0.4
6	8.4641	8.2	0.5
				7	8.2772	8.1	0.4
8	8.4462	8.2	0.5
				9	8.3612	8.2	0.5

Mean value: Y=8.2%

Mean absolute error: 8.2%-7.7%=0.5%

Average relative error: 0.5% ÷, 7.7% * 100%=6.5%

(2) difference FT-IR measures the EPR value on the same print of same sample: the results are shown in Table 3.

The same sample one print difference EPR measured value of table 3

Point on the print	FT-IR surveys the R value	FT-IR surveys Y value (EPR%)	Absolute error
				1	8.2628	8.1	0.4
2	8.4136	8.2	0.5
				3	8.3377	8.1	0.4
4	8.2659	8.1	0.4
				5	8.3834	8.2	0.5

Mean value: Y=8.2%

Mean absolute error: 8.1%-7.7%=0.4%

Average relative error: 0.4% ÷, 7.7% * 100%=5.2%

Embodiment 3 FT-IR survey EPR example and error analysis

Table 4 application example and error analysis

Claims (1)

1. the method for the second third glue content in the fast measuring ethylene, propylene COPP: it is characterized in that it is made up of following steps:

(1) measure the FT-IR infrared spectrogram of ethylene, propylene COPP with the Fourier Tranform infrared spectrometer,

(2) measure the content mass percent C of ethene in the ethylene, propylene COPP ₂ ⁼M%,

(3) from infrared spectrogram, measure the second third glue characteristic peak group 810cm ^-1, 752cm ^-1, 735cm ^-1, 730cm ^-1,

720cm ^-1The absorbance A of five absorption peaks ₈₁₀, A ₇₅₂, A ₇₃₅, A ₇₃₀, A ₇₂₀,,

(4) by formula $R={C_2}^{=}m\%\&times;(1-\frac{A_{720}}{\mathrm{\&Sigma;A}})$ Calculate the R value, wherein C ₂ ⁼M% is an ethylene, propylene

The content mass percent of ethene in the propylene is gathered in copolymerization, and ∑ A is A ₈₁₀+ A ₇₅₂+ A ₇₃₅+ A ₇₃₀+ A ₇₂₀Sum,

(5) obtain formula with at least three standard models by regression analysis

The value of A and B among the Y%=AR+B, or make typical curve, wherein Y% is the content mass percent of second third glue in the ethylene, propylene COPP,

(6) testing sample is measured the R value by above-mentioned (1) to (4) step, from typical curve, obtain the Y% value, or calculate the Y% value with formula Y%=AR+B.

Images