Fluorescence quencher, fluorescence quencher master batch as well as preparation method and application of fluorescence quencher master batch

Abstract

The invention discloses a fluorescence quencher which comprises a mixture of 5 (6)-carboxyl fluorescein diacetate N-succinimide ester and superoxide dismutase, and the weight ratio of the 5 (6)-carboxyl fluorescein diacetate N-succinimide ester to the superoxide dismutase is 1: (0.005-1). 5 (6)-carboxyl fluorescein diacetate N-succinimide ester is combined with a fluorescent substance to form a specific structure, superoxide dismutase locks the fluorescent substance through succinimide ester, and conjugated double bonds in fluorescence are directionally decomposed, so that residual fluorescence in polypropylene is directionally and efficiently decomposed and regenerated. The invention also discloses a fluorescence quenching master batch and a preparation method thereof. The fluorescence quenching master batch can be used for eliminating fluorescence in a polymer composite material.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer materials, and particularly to a fluorescence quencher, a masterbatch of fluorescence quencher, and a preparation method and application thereof. Background Art

[0002] With the rapid development of the polymer materials industry, plastic products have become an important part of production and life. As an important member of polymer materials, plastics have penetrated into all aspects of life. In 2001, the global annual consumption of plastic materials was close to 100 million tons, and the annual consumption growth rate in the past 10 years was above 10%. In 2017, the global plastic consumption reached 500 million tons. In the past three years, about 50 million tons of waste plastics have been generated in China every year, and 14 million tons of recycled plastics have not been effectively recycled. These plastics that cannot be effectively recycled return to the sea through material movement, becoming the main source of marine microplastics and causing secondary pollution. Waste plastics are difficult to decompose in the natural environment, and the fragmentation during the decomposition process causes more serious secondary pollution. Therefore, today when the human ecological environment is deteriorating day by day, the recycling of recycled plastics has attracted more and more attention. Thermoplastic resins have the characteristic of being able to be remelted and processed again. Therefore, by building a mature recycling system and reusing the resources in the wrong place, the coordinated development of economic resources, economy and environment can be achieved.

[0003] However, fluorescent substances are intentionally and unintentionally added during the synthesis and use of recycled thermoplastic resins and virgin resins. Fluorescent substances need to be completely eliminated before they can be allowed to be used in packaging products, especially packaging products that are directly or indirectly contacted by the human body. However, there is no fluorescence eliminator in the prior art to eliminate fluorescence in plastics.

[0004] Chinese invention patent CN104098747A discloses a method for preparing a fluorescence eliminator by using polymerization monomers and cellulose derivatives in the presence of metal ion chelating agents, chain transfer agents, crosslinking agents and initiators, and successfully applying it to eliminate fluorescence in paper, but it cannot be applied to eliminate fluorescence in plastics. Chinese invention patent CN 102050813 A discloses a fluorescence quencher molecule, its method and use. The invention relates to new pyridyl-isoquinoline-dione derivatives, methods for preparing these derivatives, conjugates comprising new pyridyl-isoquinoline dione derivatives and (i) a solid support or (ii) a biomolecule, methods for preparing these conjugates, and the use of these conjugates as quenchers in fluorescence resonance energy transfer (FRET). Summary of the Invention

[0005] The object of the present invention is to provide a fluorescence quencher that can be applied to eliminate fluorescence in plastics, and a masterbatch.

[0006] The present invention is realized through the following technical solutions: A fluorescence quencher, comprising a mixture of 5(6)-carboxyfluorescein diacetate N-succinimidyl ester and superoxide dismutase, with a weight ratio of 1:(0.005 - 1).

[0007] Preferably, the weight ratio of 5(6)-carboxyfluorescein diacetate N-succinimidyl ester to superoxide dismutase is 1:(0.08 - 0.10).

[0008] In order to improve the transportability of the fluorescence quencher and reduce the blending difficulty, the present invention also relates to a masterbatch of fluorescence quencher, which, by weight, comprises the following components: 5 - 20 parts of a high molecular polymer; 1 - 3 parts of a fluorescence quencher; The fluorescence quencher is a mixture of 5(6)-carboxyfluorescein diacetate N-succinimidyl ester and superoxide dismutase, with a weight ratio of 1:(0.005 - 1).

[0009] The CAS number of the 5(6)-carboxyfluorescein diacetate N-succinimidyl ester is 150347 - 59 - 4.

[0010] The CAS number of the superoxide dismutase is 9054 - 89 - 1.

[0011] Preferably, the weight ratio of 5(6)-carboxyfluorescein diacetate N-succinimidyl ester to superoxide dismutase is 1:(0.08 - 0.10).

[0012] Wherein, the high molecular polymer is selected from at least one of polyamide, polypropylene, polyethylene, polycarbonate, polyvinyl chloride, polyphenylene ether, and polysulfone.

[0013] Those skilled in the art can modify the masterbatch of fluorescence quencher according to the actual situation, such as adding 0.01 - 5 parts of an auxiliary agent, and the auxiliary agent can be an antioxidant, a lubricant, etc. These substances will not affect the fluorescence quenching effect.

[0014] Other substances, such as fillers, can also be added.

[0015] The preparation method of the masterbatch of fluorescence quencher of the present invention comprises the following steps: mixing each component evenly according to the ratio, and extruding and pelletizing through a twin-screw extruder to obtain the masterbatch of fluorescence quencher.

[0016] The application of the masterbatch of fluorescence quencher of the present invention is used to eliminate fluorescence in plastic materials.

[0017] The fluorescence comes from fluorescent agents. In the prior art, the fluorescent agents applied to plastic materials mainly include three categories: stilbene-type fluorescent agents, naphthalimide-type fluorescent agents, and coumarin-type fluorescent agents. The typical representatives of each category are respectively: Representatives of stilbene fluorescent agents are:

[0018] Representatives of naphthalimide fluorescent agents are:

[0019] Representatives of coumarin fluorescent agents are:

[0020] The above three types of fluorescent agents all produce fluorescence through conjugated double bonds, achieving the effects of enhancing the product's light brightness and blue-phase whitening. After adding such substances to the resin, without a decomposition aid with a special structure to break the double bonds, the fluorescence residue cannot be completely eliminated. And the fluorescence quencher of the present invention has excellent quenching effects on the above fluorescent agents. After eliminating the fluorescence, 5(6)-carboxyfluorescein N-succinimidyl ester will decompose and leave the succinimidyl ester functional group, and this characteristic peak can be detected by infrared spectroscopy.

[0021] The present invention has the following beneficial effects: The present invention forms a specific structure by combining 5(6)-carboxyfluorescein N-succinimidyl ester with the fluorescent agent. Superoxide dismutase locks the fluorescent substance through the succinimidyl ester and decomposes the conjugated double bonds in the fluorescence directionally, thereby efficiently decomposing the residual fluorescence in recycled polypropylene directionally, solving the problem that the recycled polypropylene with residual fluorescence after clean treatment cannot be recycled, especially being applicable to food-contact recycled plastic materials such as daily chemical packaging. The present invention also makes the fluorescence quencher into a masterbatch, which is more suitable for the application of plastic fluorescence elimination. Specific Embodiments

[0022] Examples are given below to specifically describe the present invention. It is necessary to point out here that the following examples are only used to further illustrate the present invention and cannot be understood as limiting the protection scope of the present invention. Some non-essential improvements or adjustments made by those of ordinary skill in the art to the present invention based on this example still fall within the protection scope of the present invention.

[0023] The raw materials used in the examples and comparative examples are as follows: PP: EP548R, CNOOC and Shell; Recycled PP: Transparent lunch box crushed material, with a polypropylene content of 98% and fluorescence residue; PE: HDPE 7260C, Guangdong Petrochemical; PA66: 21SPC, Solutia Inc.; PC: 3026PJ, Sanyo Chemical Industries, Ltd.

[0024] Fluorescent agent A: 7-Diethylamino-4-methylcoumarin Fluorescent agent B: 1,8-Naphthalimide-based fluorescence, Sers Beijing; Fluorescent agent C: DSD acid - triazine type stilbene, Merck Life Science; 5(6)-Carboxyfluorescein N-succinimidyl ester (abbreviated as carboxyhydroxy compound in the table): Merck Life Science; Superoxide dismutase: Merck Life Science; Antioxidant: A compound prepared by mixing hindered phenol antioxidant 1010 and phosphite antioxidant 168 in a ratio of 1:2, commercially available.

[0025] Lubricant: Calcium stearate lubricant, commercially available.

[0026] Preparation method of fluorescent plastic materials in examples and comparative examples: Mix 99.9 parts of high molecular polymer (PP, recycled polypropylene, PE, PA66, PC) and 0.1 part of fluorescent agent evenly, and extrude and pelletize through a twin-screw extruder to obtain fluorescent plastic materials.

[0027] Preparation method of fluorescent quencher masterbatch in examples and comparative examples: Mix high molecular polymer and fluorescent quencher evenly according to the ratio, and extrude and pelletize through a twin-screw extruder to obtain fluorescent quencher masterbatch.

[0028] Method for eliminating fluorescence experiment in quasi-regenerated plastics in examples and comparative examples: Mix fluorescent plastic materials and fluorescent quencher masterbatch (or fluorescent eliminator) evenly, and extrude and pelletize through a twin-screw extruder to obtain sample particles. Among them, when the plastic is PP, the temperature range of the screw is 180 - 210 °C; when the plastic is PC, the temperature range of the screw is 260 - 290 °C; when the plastic is PE, the temperature range of the screw is 130 - 180 °C; when the plastic is PA66, the temperature range of the screw is 270 - 300 °C.

[0029] Fluorescence intensity and fluorescence residue test method: Inject the sample particles or quasi-regenerated plastics into square plates and observe whether there is fluorescence under the UV lamp in a color matching light box with the naked eye. The visual fluorescence ranges from weak to strong as no fluorescence, micro fluorescence, weak fluorescence, and strong fluorescence.

[0030] Table 1: Selection of components of fluorescent plastic materials Material-1 Material-2 Material-3 Material-4 Resin type PP PE PA66 PC Fluorescent agent type A B C A Fluorescent intensity Strong fluorescence Strong fluorescence Strong fluorescence Strong fluorescence Table 2: Weight parts of components of fluorescent quencher masterbatch Masterbatch-1 Masterbatch-2 Masterbatch-3 Masterbatch-4 Masterbatch-5 Masterbatch-6 Polymer type PP PP PP PP PP PP Polymer content 10 10 10 10 5 20 Carboxyl-hydroxy compound content 1.990 1.852 1.818 1 1.818 2.727 Superoxide dismutase content 0.010 0.148 0.182 1 0.182 0.273 Continued Table 2: Masterbatch-7 Masterbatch-8 Masterbatch-9 Polymer type PE PA66 PC Polymer content 10 10 10 Carboxyl-hydroxy compound content 1.990 1.990 1.990 Superoxide dismutase content 0.010 0.010 0.010 Antioxidant 0.2 Lubricant 0.1 Table 3: Weight parts of components and test results in examples and comparative examples Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Fluorescent plastic material type Material-1 Material-1 Material-1 Material-1 Material-1 Material-1 Material-1 Fluorescent plastic material content 100 100 100 100 100 100 100 Fluorescence quencher masterbatch Masterbatch-1 Masterbatch-2 Masterbatch-3 Masterbatch-4 Masterbatch-1 Masterbatch-5 Masterbatch-6 Fluorescence quencher masterbatch content 0.25 0.25 0.25 0.25 0.35 0.2 0.77 Carboxyl-hydroxy compound content - - - - - - - Superoxide dismutase content - - - - - - - Fluorescence residue Micro-fluorescence No fluorescence No fluorescence Micro-fluorescence No fluorescence No fluorescence No fluorescence As can be seen from Examples 1-4, the fluorescence elimination performance is better when the weight ratio of fluorescein 5(6)-carboxy diacetate N-succinimidyl ester to superoxide dismutase is optimized.

[0031] As can be seen from Example 1 / 5, the fluorescence can be completely eliminated by increasing the content of the fluorescent quencher masterbatch.

[0032] Continued Table 3: Example 8 Example 9 Example 10 Example 11 Fluorescent plastic material type Material-2 Material-3 Material-4 Material-1 Fluorescent plastic material content 100 100 100 100 Fluorescence quencher masterbatch Masterbatch-7 Masterbatch-8 Masterbatch-9 - Fluorescence quencher masterbatch content 0.7 0.7 0.7 - Carboxyl-hydroxy compound content - - - 0.091 Superoxide dismutase content - - - 0.009 Fluorescence residue No fluorescence No fluorescence No fluorescence No fluorescence Continued Table 3: Example 12 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Fluorescent plastic material type Recycled PP Material-1 Material-2 Material-3 Material-4 Recycled PP Fluorescent plastic material content 100 100 100 100 100 100 Fluorescence quencher masterbatch Masterbatch-1 - - - - - Fluorescence quencher masterbatch content 0.45 - - - - - Carboxyl-hydroxy compound content - - - - - - Superoxide dismutase content - - - - - - Fluorescence residue No fluorescence Strong fluorescence Strong fluorescence Strong fluorescence Strong fluorescence Weak fluorescence As can be seen from the examples, when the total amount of the fluorescent quencher in this application ≥ the amount of the fluorescent agent, the fluorescence can be significantly reduced. The fluorescence elimination effect is better with the optimized ratio of the fluorescent quencher. Moreover, the fluorescent quencher in this application has a good quenching effect on commonly used fluorescent agents.

Claims

1. A fluorescence quenching agent, characterized in that, it comprises a mixture of 5(6)-carboxyfluorescein N-succinimidyl ester and superoxide dismutase, and the weight ratio is 1:(0.005 - 1).

2. The fluorescence quenching agent according to claim 1, characterized in that, the weight ratio of 5(6)-carboxyfluorescein N-succinimidyl ester to superoxide dismutase is 1:(0.08 - 0.10).

3. A masterbatch of fluorescence quenching agent, characterized in that, by weight, it comprises the following components: 5 - 20 parts of high molecular polymer; 1 - 3 parts of fluorescence quenching agent; the fluorescence quenching agent is a mixture of 5(6)-carboxyfluorescein N-succinimidyl ester and superoxide dismutase, and the weight ratio is 1:(0.005 - 1).

4. The masterbatch of fluorescence quenching agent according to claim 3, characterized in that, the weight ratio of 5(6)-carboxyfluorescein N-succinimidyl ester to superoxide dismutase is 1:(0.08 - 0.10).

5. The masterbatch of fluorescence quenching agent according to claim 3, characterized in that, the high molecular polymer is selected from at least one of polyamide, polypropylene, polyethylene, polycarbonate, polyvinyl chloride, polyphenylene ether, polysulfone.

6. The masterbatch of fluorescence quenching agent according to claim 3, characterized in that, by weight, it further comprises 0.01 - 5 parts of auxiliary agent, and the auxiliary agent is selected from at least one of antioxidant and lubricant.

7. The preparation method of the masterbatch of fluorescence quenching agent according to any one of claims 3 - 6, characterized in that, it comprises the following steps: according to the ratio, mix each component evenly, and extrude and pelletize through a twin-screw extruder to obtain the masterbatch of fluorescence quenching agent.

8. The application of the masterbatch of fluorescence quenching agent according to any one of claims 3 - 6, characterized in that, it is used to eliminate the fluorescence in plastic materials, and the fluorescence comes from fluorescent agents, and the fluorescent agents are selected from at least one of stilbene-type fluorescent agents, naphthalimide-type fluorescent agents, coumarin-type fluorescent agents.