CN105067726B - The assay method of isocyanate content in a kind of plastic sample - Google Patents

Abstract

The present invention discloses a kind of method for determining isocyanate content in plastic sample, comprises the following steps：Weigh sample to be put into container, add organic solvent, internal standard substance and derivating agent, wrap up test tube with aluminium-foil paper, it is to avoid illumination；Test tube cap plug is positioned on oscillator, shakes 10~24h；Repeat the above steps once, then extract will merge twice；Solvent is dried up with nitrogen at room temperature, with acetonitrile and water dissolved residue, filtering；Determine the isocyanate content in solution.The assay method of the present invention, the pretreatment time of plastic sample in traditional assay method is greatly reduced, while the accuracy rate and stability of measure are ensure that, and simple to operate, reliable results, test medicine consumption is saved, it is with low cost.

Description

The assay method of isocyanate content in a kind of plastic sample

Technical field

The present invention relates to chemical field, the assay method of isocyanate content in more particularly to a kind of plastic sample.

Background technology

Packaging material for food and textile industry usually use substantial amounts of artificial synthesized polymeric material, such as various performances are excellent Good plastics.These materials be often required to food or human contact, with the raising of people's quality of the life, people are increasingly closed Note the poisonous and harmful substance remained in these artificial synthesized materials.Isocyanates is used as one of raw material of synthetic plastic, its poison Property after being widely known by the people, people are also increasingly paid close attention to its residual, and European Union contacts plastics and plastics to isocyanates in food Use in production of articles is made that relevant regulations, according to this regulation, and the content of isocyanates residue is not in plastic products 1.0mg/kg must be higher than.And method of testing current at present is extracted by dichloromethane, derivating agent is glimmering with efficient liquid phase after deriving Light is detected, it is necessary to which by changing different mobile phase and chromatographic column carries out qualitative, method is cumbersome and is not suitable in laboratory Carry out high flux screening test.At present, for the detection of isocyanate content in plastic sample, even SGS, PSB, ITS these International professional testing agency is also both referred to the standard EN13130-8 of European Union:2008.But, it is preceding during with reference to EN13130 Processing time not only up to twenties hours, and every time detection once appearance can be after result, in addition it is also necessary to different colors Spectrum column chromatography condition is confirmed repeatedly, while also to need to be repeated to do again with standard addition method sample so as to accurate quantitative analysis knot Really, chemical reagent because that need to make sample so that consumption is very big, and consumes substantial amounts of manpower and time repeatedly.Though institute is in this way Isocyanates can be so measured, but be not suitable for common laboratory and use.

The content of the invention

The present invention proposes that a kind of energy is simple, quick, disposable accurate qualitative, quantitative determines isocyanates in plastic sample and contains The chemical method of amount.To solve detection at present, time-consuming, cost high, complex operation, it is impossible to the technical problem such as batch processing sample. The present invention adopts the following technical scheme that solution above-mentioned technical problem：

A kind of method of isocyanate content in measure plastic sample, it is characterised in that comprise the following steps:

Weigh sample to be put into container, add organic solvent, internal standard substance and derivating agent, wrap up test tube with aluminium-foil paper, keep away Exempt from illumination；

Test tube cap plug is positioned on oscillator, shakes 10~24h；

Repeat the above steps once, then extract will merge twice；

Solvent is dried up with nitrogen at room temperature, with acetonitrile and water dissolved residue, filtering；

Determine the isocyanate content in solution.

It is preferred that, in a kind of above-mentioned measure plastic sample in the method for isocyanate content, the organic solvent is Dichloromethane.

It is preferred that, in a kind of above-mentioned measure plastic sample in the method for isocyanate content, the derivating agent is just Butylamine.

It is preferred that, in a kind of above-mentioned measure plastic sample in the method for isocyanate content, during the concussion reaction Between be 12h.

It is preferred that, in a kind of above-mentioned measure plastic sample in the method for isocyanate content, use efficient liquid phase string Join the isocyanate content in mass spectrograph measure solution.

Compared with prior art, the present invention has the advantages that：

1st, after deriving compared to common method derivating agent, qualitative, this method matter is carried out with efficient liquid phase fluorescence detector It is qualitative more reliable accurate to compose, more simple and efficient.

2nd, using efficient liquid phase tandem mass spectrum the characteristics of, two or more ion pair is selected, more accurate is judged to result, detection Limit is also lower.

3rd, the content of isocyanates is determined using efficient liquid phase tandem mass spectrometry, its testing result is quick, accurately.

Embodiment

The technical scheme in the embodiment of the present invention is clearly described below.Obviously, described embodiment is only It is a part of embodiment of the invention, rather than whole embodiments.Based on the embodiment in the present invention, ordinary skill people The every other embodiment that member is obtained under the premise of creative work is not made, belongs to the scope of protection of the invention.

Embodiment 1：Weigh 20 parts of negative plastic samples of 0.5g typical cases

Do following experiment：Take wherein 10 parts samples to be put into 20ml test tube, add 10ml dichloromethane, be separately added into 50ul 1ug/ml 9 kinds of isocyanates mixed solutions, and appropriate internal standard substance and derivating agent, derivating agent is preferably just Butylamine, to avoid illumination with aluminium-foil paper parcel test tube, covers plug, test tube is put into continuous concussion 12h on the oscillator, by solution Take out, 10ml dichloromethane is added again, then is extracted once, solution will merge twice, then at room temperature with nitrogen by solution Drying, then adds appropriate acetonitrile and the aqueous solution, after filtering, sample is detected with efficient liquid phase tandem mass spectrometry, surveys Determine the content of isocyanates in solution.It the results are shown in Table 1 and table 3；Other 10 parts of samples are tested using prior art, institute Survey the results are shown in Table 2 and table 4.By taking 2,6-Toluene diisocyanate and 2,4-Toluene diisocyanate as an example, by Analysis result knows that the average recovery rate of method of the invention is 92~98%, and what significantly larger than art methods were measured is averaged The rate of recovery 74~85%；In addition, being 0.001mg/kg using ten testing standard deviations of the method for the present invention, less than using existing There is the standard deviation 0.003mg/kg of technical method, thus illustrate that the method for the present invention is more stablized.

The 2,6-Toluene diisocyanate contents that table 1 is measured using the method for the present invention

The 2,6-Toluene diisocyanate contents that table 2 is measured using prior art

The 2,4-Toluene diisocyanate contents that table 3 is measured using the method for the present invention

Sample number	Test result (mg/kg)	The rate of recovery
			1	0.093	93%
2	0.091	91%
			3	0.094	94%
4	0.091	91%
			5	0.094	94%
6	0.092	92%
			7	0.09	90%
8	0.091	91%
			9	0.095	95%
10	0.093	93%
			Average value	0.0924	92.4%
Standard deviation	0.001

The 2,4-Toluene diisocyanate contents that table 4 is measured using prior art

By data above, assay method of the invention, by the pretreatment time of plastic sample in traditional assay method Greatly reduce, while the accuracy rate and stability of measure are ensure that, and simple to operate, reliable results, test medicine consumption is saved, It is with low cost.

The foregoing is merely illustrative of the preferred embodiments of the present invention, is not intended to limit the invention, all essences in the present invention Any modifications, equivalent substitutions and improvements made within refreshing and principle etc., should be included in the scope of the protection.

Claims (2)

1. a kind of method for determining isocyanate content in plastic sample, it is characterised in that comprise the following steps：

Weigh sample to be put into container, add dichloromethane, internal standard substance and derivating agent n-butylamine, test tube is wrapped up with aluminium-foil paper, Avoid illumination；

Test tube cap plug is positioned on oscillator, shakes 10~24h；

Repeat the above steps once, then extract will merge twice；

Solvent is dried up with nitrogen at room temperature, with acetonitrile and water dissolved residue, filtering；

The isocyanate content in solution is determined using efficient liquid phase tandem mass spectrometer.

2. a kind of method for determining isocyanate content in plastic sample according to claim 1, it is characterised in that：It is described The concussion reaction time is 12h.