A closed porous composite material and a manufacturing method thereof. The method comprises: 1) preparing a mixture, wherein the mixture comprises 30 to 70 parts by weight of water-dispersed resin, 10 to 300 parts by weight of unexpanded thermal expansion microspheres, and 100 to 550 parts by weight of water, and stirring the mixture thoroughly; 2) preparing a carrier; 3) coating the carrier with the mixture acquired in step 1; 4) heating the carrier for a certain period of time, such that during heating, the unexpanded thermal expansion microspheres expand; and 5) repeating steps 3 and 4 multiple times to acquire a closed porous composite material. The closed porous composite material comprises a large number of closed cavities and polymer walls separating the closed cavities from each other, such that a size range of the closed cavity is 20 µm to 800 µm, and the ratio of a total volume of the closed cavities to a total volume of the polymer walls is greater than 16.
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