A modified polysiloxane has formula (I) In formula (I) m is an integer between 0 and 10000; n is an integer between 0 and 10000; m and n cannot be equal to 0 simultaneously; R1-R7 are the same or different; and at least one of R1-R7 includes a group having a reversible chemical bond system based on a hydrogen bond, a coordinate bond, or a covalent bond. The polysioxane is used as a main chain to introduce a reversible chemical bond having temperature sensitivity by using a chemical method, so as to obtain a polymer material which is highly sensitive to temperature. The temperature-sensitive properties of materials provide functional materials for specific applications, such as medical external fixation materials, orthopedic materials, and packaging materials, can be obtained by using particular processing and preparation methods.