Recent progress in photoinitiated ring-opening metathesis polymerization (photo-ROMP) has enabled the lithographic production of patterned films from olefinic resins. The use of a latent ruthenium catalyst (e.g., HeatMet) in combination with a photosensitizer (e.g., 2-isopropylthioxanthone) to rapidly photopolymerize metathesis-monomers (e.g., dicyclopentadiene (DCPD)) upon irradiation with UV light has previously been demonstrated. See U.S. application Ser. No. 17/677,558. In addition to the exemplary catalysts and photosensitizers described in that work, a variety of alternative catalysts and photosensitizers are commercially available that allows for tuning of thermomechanical properties, potlifes, activation rates, and irradiation wavelengths. As an example, fourteen catalysts and eight photosensitizers were surveyed for the photo-ROMP of DCPD and the structure-activity relationships of the catalysts examined. Properties relevant to photopolymerization-based additive manufacturing—potlifes, printing irradiation dose, conversion—were characterized to develop catalyst and photosensitizer libraries. Two optimized catalyst/photosensitizer systems were demonstrated in the rapid stereolithographic printing of complex, multidimensional pDCPD structures with microscale features under ambient conditions.

A polymer compound including a repeating unit represented by Formula: ##STR00001##
wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4, a1, a2, and a11 in Formula 1 are as defined in the specification.

A polymer compound including a repeating unit represented by Formula: ##STR00001##
wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4, a1, a2, and a11 in Formula 1 are as defined in the specification.

The present disclosure relates to a composition that includes ##STR00001##
where R.sub.1 and R.sub.2 include at least one of a hydrogen, a hydroxyl group, and/or an alkyl group, R.sub.3 and R.sub.4 include at least one of hydrogen, a hydroxyl group, an alkyl group, and/or a ketone, and 1≤n≤2000.

The present disclosure relates to a composition that includes ##STR00001##
where R.sub.1 and R.sub.2 include at least one of a hydrogen, a hydroxyl group, and/or an alkyl group, R.sub.3 and R.sub.4 include at least one of hydrogen, a hydroxyl group, an alkyl group, and/or a ketone, and 1≤n≤2000.

A cycloolefin ring-opened copolymer includes a structural unit derived from a norbornene compound that includes a heteroelement-containing hydrocarbon group and a structural unit derived from a norbornene compound that includes a heteroelement-free hydrocarbon group. In this copolymer, the structural unit derived from the norbornene compound that includes the heteroelement-containing hydrocarbon group has a proportional content of not less than 0.01 mol % and not more than 15.00 mol % when all structural units included in the copolymer are taken to be 100 mol %.

A method of rapidly forming an elastomer with tunable properties is described herein. The method includes preparing a monomer solution comprising a catalyst and one or more monomers including 1,5-cyclooctadiene (COD). The one or more monomers may further include dicyclopentadiene (DCPD), and each of the COD and the DCPD may be present in the monomer solution at a predetermined volume percentage. A region of the monomer solution is activated to initiate an exothermic polymerization reaction and generate a self-propagating polymerization front, which moves through the monomer solution and polymerizes the one or more monomers. Thus, an elastomer having predetermined properties is rapidly formed.

A method of rapidly forming an elastomer with tunable properties is described herein. The method includes preparing a monomer solution comprising a catalyst and one or more monomers including 1,5-cyclooctadiene (COD). The one or more monomers may further include dicyclopentadiene (DCPD), and each of the COD and the DCPD may be present in the monomer solution at a predetermined volume percentage. A region of the monomer solution is activated to initiate an exothermic polymerization reaction and generate a self-propagating polymerization front, which moves through the monomer solution and polymerizes the one or more monomers. Thus, an elastomer having predetermined properties is rapidly formed.

Formamide group-containing monomers and polymers made by polymerizing the monomers are provided. Also provided are methods of polymerizing the monomers and methods of synthesizing functionalized polymers by pre- and/or post-polymerization functionalization. The monomers are non-toxic and can generate highly reactive isocyanate and isonitrile precursors in a one-pot synthesis that enables the incorporation of complex functionalities into the side-chain of the polymers that are synthesized from the monomers.

The invention is directed to the selective dual wavelength olefin metathesis polymerization for additive manufacturing. Dual-wavelength stereolithographic printing uses ring-opening metathesis polymerization of the metathesis-active polymers. As an example, a resin formulation based on dicyclopentadiene was produced using a photolatent olefin metathesis catalyst, various photosensitizers and photobase generators to achieve efficient initiation by light at one wavelength (e.g., blue) and fast catalyst decomposition and polymerization deactivation by light at a second wavelength (e.g., ultraviolet). This process enables 2-dimensional stereolithographic printing, either using photomasks or with patterned, collimated light. Importantly, the same process was readily adapted for 3-dimensional continuous additive manufacturing, with printing rates of up to 36 mm h.sup.−1 for patterned light and up to 180 mm h.sup.−1 using un-patterned, high intensity light.