Method for preparing monodisperse polymer nano-microspheres

Abstract

The invention relates to a method for preparing high-monodispersity polymer nano-microspheres. By adopting innovative measures of adding surfactant in a concentration lower than critical micelle concentration to a polymerization reaction system, stabilizing primary particles generated by homogeneous nucleation in an early stage of polymerization, introducing an appropriate amount of polar solventto improve the critical micelle concentration of the surfactant in a dispersion medium and increase the solubility of monomers in the dispersion medium, and the like, the method effectively increasesthe stability of the primary particles generated by homogeneous nucleation in the early stage of polymerization, shortens polymerization time, and finally obtains polymer microspheres which have particle size less than 100 nm and are highly uniform in size distribution. The method is different from soap-free emulsion polymerization and conventional emulsion polymerization methods, simple in preparation process and easy to control, and the obtained polymer nano-microspheres are excellent in monodispersity. The products of each batch are good in reproducibility, so the method is easy to realizeindustrialization.

Description

technical field

[0001] The invention relates to a method for preparing monodisperse polymer nanospheres, in particular to a simple and efficient method for preparing highly monodisperse polymer nanospheres, which can be widely used in biological sciences, medical diagnosis and treatment, electronics and Optoelectronics science, standard metrology, chromatographic analysis and other fields. Background technique

[0002] Monodisperse polymer nanospheres refer to polymer microspheres with the same particle shape, diameter <100nm, and uniform size distribution. In recent years, due to the wide application of polymer microspheres in biological science, medical diagnosis and treatment, electronic and optoelectronic device technology, more and more people pay more and more attention, and the preparation methods involved are also various.

[0003] Soap-free emulsion polymerization is a very effective method for preparing monodisperse polymer microspheres. However, since no surf...

Examples

Embodiment 1

[0026] In a 250mL three-necked flask equipped with a condenser, add 96mL of deionized water and 0.17g of sodium lauryl sulfate to form a transparent solution. During stirring, 2.5 mL of styrene was added. Nitrogen was passed for 15 minutes, and the reaction system was heated to raise the temperature to 70°C. Then add 4 mL of an aqueous solution containing 0.13 g of potassium persulfate, stir at 200 rpm, and react for 4 hours to obtain monodisperse polystyrene microspheres with a diameter of 77 nm and a PDI of 1.005. Its typical scanning electron microscope pictures are as follows: figure 1 As shown, the average diameter of the microspheres is 77 nm, and the PDI is 1.005.

Embodiment 2

[0028] In a 250mL three-necked flask equipped with a condenser, add 96mL of deionized water and 0.09g of sodium dodecylsulfonate to form a transparent solution. During stirring, 10 mL of methyl methacrylate was added. Nitrogen was passed for 15 minutes, and the reaction system was heated to raise the temperature to 80°C. Then add 4 mL of an aqueous solution containing 0.09 g of potassium persulfate, stir at a speed of 300 rpm, and react for 3 hours to obtain monodisperse polymethyl methacrylate microspheres with an average diameter of 59 nm and a PDI of 1.01. Its typical scanning electron microscope pictures are as follows: figure 2 As shown, the average diameter of the microspheres is 59 nm, and the PDI is 1.01.

Embodiment 3

[0030] In a 250mL three-necked flask equipped with a condenser, add 71mL of deionized water, 32mL of absolute ethanol, and 0.45g of dodecyltrimethylammonium bromide to form a transparent solution. During stirring, 2.5 mL of divinylbenzene was added. Nitrogen was passed for 15 minutes, and the reaction system was heated to raise the temperature to 60°C. Then add 4 mL of an aqueous solution containing 0.13 g of ammonium persulfate, stir at 400 rpm, and react for 2 hours to obtain monodisperse polydivinylbenzene microspheres with a diameter of 61 nm and a PDI of 1.01.

technical field

[0001] The invention relates to a method for preparing monodisperse polymer nanospheres, in particular to a simple and efficient method for preparing highly monodisperse polymer nanospheres, which can be widely used in biological sciences, medical diagnosis and treatment, electronics and Optoelectronics science, standard metrology, chromatographic analysis and other fields. Background technique

[0002] Monodisperse polymer nanospheres refer to polymer microspheres with the same particle shape, diameter <100nm, and uniform size distribution. In recent years, due to the wide application of polymer microspheres in biological science, medical diagnosis and treatment, electronic and optoelectronic device technology, more and more people pay more and more attention, and the preparation methods involved are also various.

[0003] Soap-free emulsion polymerization is a very effective method for preparing monodisperse polymer microspheres. However, since no surf...

Examples

Embodiment 1

[0026] In a 250mL three-necked flask equipped with a condenser, add 96mL of deionized water and 0.17g of sodium lauryl sulfate to form a transparent solution. During stirring, 2.5 mL of styrene was added. Nitrogen was passed for 15 minutes, and the reaction system was heated to raise the temperature to 70°C. Then add 4 mL of an aqueous solution containing 0.13 g of potassium persulfate, stir at 200 rpm, and react for 4 hours to obtain monodisperse polystyrene microspheres with a diameter of 77 nm and a PDI of 1.005. Its typical scanning electron microscope pictures are as follows: figure 1 As shown, the average diameter of the microspheres is 77 nm, and the PDI is 1.005.

Embodiment 2

[0028] In a 250mL three-necked flask equipped with a condenser, add 96mL of deionized water and 0.09g of sodium dodecylsulfonate to form a transparent solution. During stirring, 10 mL of methyl methacrylate was added. Nitrogen was passed for 15 minutes, and the reaction system was heated to raise the temperature to 80°C. Then add 4 mL of an aqueous solution containing 0.09 g of potassium persulfate, stir at a speed of 300 rpm, and react for 3 hours to obtain monodisperse polymethyl methacrylate microspheres with an average diameter of 59 nm and a PDI of 1.01. Its typical scanning electron microscope pictures are as follows: figure 2 As shown, the average diameter of the microspheres is 59 nm, and the PDI is 1.01.

Embodiment 3

[0030] In a 250mL three-necked flask equipped with a condenser, add 71mL of deionized water, 32mL of absolute ethanol, and 0.45g of dodecyltrimethylammonium bromide to form a transparent solution. During stirring, 2.5 mL of divinylbenzene was added. Nitrogen was passed for 15 minutes, and the reaction system was heated to raise the temperature to 60°C. Then add 4 mL of an aqueous solution containing 0.13 g of ammonium persulfate, stir at 400 rpm, and react for 2 hours to obtain monodisperse polydivinylbenzene microspheres with a diameter of 61 nm and a PDI of 1.01.

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