Mosquito repellent composition, preparation method and application thereof

A mosquito repellent composition, comprising the following ingredients and mass fractions thereof:

• composite plant oil 7-10 parts, gromwell root extracts 3-5 parts, Vitex rotundifolia extracts 1-3 parts, sustained release agents 1-2 parts, emulsifying agents 2-4 parts, stabilizing agent 0.1-0.3 part, and water 165-182 parts;
• wherein the composite plant oil is made from Carapa guianensis seed oil and bergamot orange oil at a mass ratio of 4-6:3-5;
• wherein the sustained release agents are made from nano-meter attapulgite, polyvinyl alcohol and chitosan oligosaccharide at a mass ratio of 1-2:5-7:12-15;
• wherein the emulsifying agents are made from alkyl glycoside and cetearyl glucoside at a mass ratio of 2-3:5-8;
• wherein the stabilizing agent is carbomer 940;
• wherein a preparation method of the gromwell root extracts is:
• (1) grinding gromwell roots, filtering with a 50-80-mesh filter, and obtaining coarse gromwell root powder;
• (2) chilling the coarse gromwell root powder obtained in step (1) at a chilling temperature of 0-4° C. for 4-6 h and obtaining chilled coarse gromwell root powder;
• (3) grinding the chilled coarse gromwell root powder obtained in step (2), filtering with a 100-150-mesh filter and obtaining fine gromwell root powder;
• (4) putting the fine gromwell root powder obtained in step (3) in a container,
• (5) adding ethanol water solution with a mass of the ethanol water solution 8-15 times the mass of the fine gromwell root powder, and extracting by ultrasonic extraction at an ultrasonic power of 100-200 W for 7-12 min,
• (6) filtering until no ethanol flavor is perceived, and
• (7) obtaining the gromwell root extracts.