Abstract: Tunable negative thermal expansion linear polymer materials with reversible large-scale mechanoresponse under low-energy stimulation and fabrication methods are provided. The reversible thermal contraction of the material is due to a molecular switch, s-dibenzocyclooctadiene (DBCOD), which undergoes a twist-boat to chair conformational change when heated or radiated by near-infrared light. The DBCOD moieties are present as either crosslinkers or polymer main-chain units and the corresponding polymers can have different amounts of DBCOD units in the polymer main chain. The various DBCOD monomers can be covalently incorporated into a variety of polymeric materials to construct negative thermal expansion or zero expansion materials for the specific applications.