Latent ROMP monomers and use thereof

Abstract

Quadricyclane-based latent ROMP monomer is provided. Polymerizable compositions comprising thereof and method of synthesizing ROM polymers using same are also disclosed.

Description

LATENT ROMP MONOMERS AND USE THEREOFCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of priority of U.S. Provisional Patent Application No. 63 / 698,084 filed September 24, 2024, titled "Controlled polymerization of photoswitchable olefins: A new paradigm of latent ROMP monomers". The contents of the application are all incorporated herein by reference in their entirety.FIELD OF THE INVENTION

[0002] The invention relates generally to the field of monomers for ring-opening metathesis polymerization (ROMP), articles comprising same and methods of synthesizing ring-opening metathesis polymers using the monomers disclosed herein.BACKGROUND OF THE INVENTION

[0003] Polymers are decidedly amongst the most pervasive materials we depend on today for our daily lives. They are ubiquitous both in biology and industry, taking on a variety of distinct functions, from storing information to enabling tough durable materials. The rich diversity of polymer applications stems from the vast space of possible microstructures and their direct impact on bulk properties. More than a century has passed since the birth of polymer science was stapled by the classic publication of Hermann Staudinger’s, “Uber Polymerisation”, where it was claimed that the outstanding mechanical properties of natural rubber were derived from the long chains in the molecular structure.1 Since this seminal work introducing the concept of macromolecules, great leaps have been made in our understanding of polymerization systems and a diverse synthetic toolbox has been developed to manipulate them.

[0004] The current state-of-the-art includes an ever-growing cache of monomers that can be assembled into sophisticated architectures, with catalysts and initiators enabling exceptional efficiency and precision. Among the pending challenges at the forefront of polymer chemistry is the development of methods that enable spatial and temporal control over polymerization reactions.

[0005] Olefin metathesis is a powerful tool in organic synthesis in general and in polymer chemistry in particular. The advent of stable Ru-based olefin metathesis by Grubbs and co-workers attracted great interest, leading to the development of a plethora of catalysts designed forspecialized applications. The effort to introduce spatial and temporal resolution to polymerization systems was not overlooked by scientists working in this field. Thus, a diverse range of techniques have been utilized to impart latency to metathesis catalysts. For example, the Grubbs group developed a catalyst stimulated by the activation of a photoacid, capable of polymerizing different monomers. In another work, modification of the cyclic alkyl amino carbene on the ruthenium catalyst with an azobenzene, afforded a photoswitchable ring-opening metathesis polymerization (ROMP) system.

[0006] However, the state-of the-art is completely silent with respect to industrially applicable “latent” ROMP monomers characterized by a sufficient storage shelf-life even in a mixture with a ROMP catalyst and which can be easily activated to induce on-demand polymerization.BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Fig. 1 is a scheme showing utilization of NBD / QC interconversion as a platform for the development of a latent monomer polymerization.

[0008] Figs. 2A-2I present schemes and graphs of Photoisomerization of NBD to QC and thermal retro-cycloaddition (RCA). 2A, NBD - QC isomerization cycle, the deactivation or “off’ reaction ([2+2] photocycloaddition) is highlighted. 2B, Conversion of NBD to QC calculated from integration of NMR peaks as a function of UV (313 nm) irradiation time. Red and blue curves represent the conversion to QCi and QC2, respectively. 2C, Structures of QCi and QC2, highlighting derivatization of QC with different esters. 2D, NBD - QC isomerization cycle, the activation or “on” reaction (RCA) is highlighted. 2E, Conversion of QC to NBD calculated from integration of NMR peaks as a function of reaction time. 2F, Red curves represent the results for photothermal heating with AuBPsso (5 OD), while the blue curves represent the results for conventional heating with a hotplate (AuBPsso also included in these experiments). 2G, NMR conversion of QCi to NBDi after 5 hours at different reaction temperatures. 2H, NMR conversion of QCi to NBDi after 5 hours as a function of AuBPsso concentration with PTH (red) or CHeat (blue). The left column showing 0 OD i.e. without AuBPs, was performed for PTH, but temperature reached 35 °C and no conversion was observed. 21, Initial stage of the temperature ramping profiles for the reactions shown in h.

[0009] Figs. 3A-3C present schemes and graphs of photothermal acceleration of RCA rate. 3A, NMR conversion of QCi to NBDi with PTH (red) and CHeat (blue) after 5 hours at 100 °C. Onthe left with white background, experiments in solution (0.1 M QCi), solvent and AuBP type (5 OD) written below columns. On the right with blue background, experiments without solvent (neat), written below monomer and AuBP (5 OD) type. 3B, NMR conversion of QCi to NBDi after 5 hours at 100 °C as a function of QCi concentration. Red curves for PTH, blue for CHeat. Dashed lines for DMSO and solid lines for toluene. 3C, Illustration of AuBP initiating the RCA of a surrounding layer of QC molecules, followed by reaction propagation assisted by the heat produced both from the exothermic transition and the thermoplasmonic nanoparticle excitation.

[0010] Figs. 4A-4G present graphs and schemes of thermal and photothermal polymerization of latent monomer. 4A, Reaction scheme of QC polymerization. First, the RCA of QC to NBD is initiated by PTH or CHeat, as this occurs NBD starts to undergo ROMP with the presence of a Ru olefin metathesis catalyst. 4B, Polymer yield and the time when polymers become insoluble as a function of temperatures for different monomer and heating methods. Blue axis corresponds to columns showing polymer yield as calculated from NMR spectra. Red axis corresponds to points in time when polymer samples became insoluble. 4C, Mixture composition as a function of reaction progress. Initially, only QC2 is present, once the temperature is elevated and the reaction starts polymer and NBD2 start to form. 4D, As c but with CHeat instead of PTH. 4E, Polymer formation with different HG-II loadings. 4F, Polymer formation with different catalysts, Bis- CAAC (red) and HG-II (green). 4G, Graph comparing polymer formation with different QC diester substituents: QCi (green), QC2 (red), and QC3 (blue). Reactions shown in 4C-G were carried out with AUBP85O (5OD), HG-II (1 mol%) and QC2 (neat), at 80 °C unless otherwise specified.[Oi l] Figs. 5A-5C present graphs and schemes showing interaction between latent monomer and catalyst. 5A, Scheme showing the strategies used to prevent ROMP during RCA. Above, the tetrasubstituted NBD double bond cannot polymerize. Below, diiodo catalyst and RuCh cannot initiate polymerization. 5B, Formation of NBDtet at 100 °C over time. Blue curve, reaction carried out in the presence of HG-II (1 mol%). Red curve, reaction carried out without catalyst. 5C, Formation of NBDi and polymer with different additives at 80 °C after 24 hours.

[0012] Figs. 6A-6G present graphs and schemes showing Application of the latent monomer to unique polymerization systems. 6A, One pot synthesis of di-block copolymer with NBDi, as a conventional monomer, and QC2, a latent monomer. The reaction is carried out without solvent and with one equivalent of QC2 and two of NBDi (1 mol% HG-II according to QC2 concentration, 5 OD AUBP85O). 6B, NMR spectra of di-block copolymer synthesis at different stages. Dark blue,T=0, NMR before addition of catalyst. Blue, T=10 minutes, NMR after completion of first NBDi block. Light blue, T=30 minutes, NMR after irradiation at 850 nm to 80 °C for 20 minutes. 6C, SEC data on polymer chain size for the intermediate / w / y-NBDi product and the final di -block copolymer. 6D, Reaction scheme for sequential polymerization of Janus type monomer. Color and shapes corresponding to NMR spectra in 6E. 6E, Dark blue, T=0, NMR before addition of catalyst. Blue, T=1 hour, NMR after completion of ADMET step. 6F, Illustration of light patterning technique including LED, custom mask, microscope slide and formulation spread. 6G, Top, polymer structure and digital and thermal images of polymer patterning using a formulation of QCi, HG-II (1 mol%) and AuBPsso (5 OD). Bottom, polymer structure and digital and thermal images of polymer patterning using a formulation of QC4 after ADMET step, HG-II (5 mol%) and AuBPsso (5 OD). Scale bar at 10 mm.

[0013] Figure 7 is a TEM image of an exemplary plasmonic material disclosed herein - AuBPs that adsorb light in the IR range (AuBP850). The darker shape is the gold bipyramid, the rounded grey shape is the silica shell.SUMMARY

[0014] The following embodiments and aspects thereof are described and illustrated in conjunction with systems, tools and methods which are meant to be exemplary and illustrative, not limiting in scope.

[0015] In one aspect of the invention, there is provided a polymerizable composition comprising a latent ring-opening metathesis polymerization (ROMP) precursor and a ROMP catalyst, wherein said latent ROMP precursor is represent by Formula 1 :wherein each of R1 and R2 is independently selected from H, optionally substituted alkyl, optionally substituted alkenyl, -C(=O)OR, -C(=S)OR, -C(=NH)OR, - C(=O)NHR, -C(=S)NHR and -C(=NH)NHR, or wherein R1 and R2 are interconnected to form a 4-8 membered saturated or unsaturated ring; wherein R is selected from H, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted cycloalkyl, optionally substituted heterocyclyl, optionally substituted aryl, optionally substituted heteroaryl and optionallysubstituted alkyl-cyclyl; wherein said cyclyl is selected from cycloalkyl, heterocyclyl, aryl and heteroaryl.

[0016] In one embodiment, ROMP catalyst is present in the polymerizable composition at an amount of between 0.1 and 50mol%, relative to the latent ROMP precursor.

[0017] In one embodiment, the polymerizable composition comprising a plasmonic material.

[0018] In one embodiment, the plasmonic material is characterized by a photothermal activation wavelength in a range between 400 and 1200 nm or between 200 and 1200 nm; and wherein said plasmonic material is in a form of a plurality of nanoparticles each nanoparticle is a plasmonic Au nanoparticle encapsulated by an oxide shell; optionally wherein said plurality of nanoparticles is characterized by an average particle size between 100 nm and 500um, determined based on TEM image.

[0019] In another aspect, there is provided a method of synthesizing a ROM polymer, comprising providing the polymerizable composition of the invention; and inducing isomerization of the latent ROMP precursor to a norbornadiene isomer thereof, thereby obtaining the ROM polymer.

[0020] In one embodiment, the polymerizable composition is the composition of the invention; and wherein said inducing isomerization comprises a light irradiation sufficient for inducing a photothermal activation of said plasmonic material.

[0021] In another aspect, there is provided a compound represented by Formula 2:wherein each of R1 and R2 is independently optionally substituted alkenyl, - C(=O)OR, -C(=S)OR, -C(=NH)OR, -C(=O)NHR, -C(=S)NHR and -C(=NH)NHR, or wherein Rl and R2 are interconnected to form a 4-8 membered unsaturated ring; wherein R is optionally substituted alkenyl.

[0022] In one embodiment, the Rl and R2 represent the same or different substituents, and wherein each of Rl and R2 is -C(=O)OR; and wherein R is optionally substituted C2-C10 alkenyl.

[0023] A method of synthesizing a ROM polymer, comprising providing a composition comprising the compound of the invention, a ROMP catalyst and a plasmonic material; inducing acyclic diene metathesis (ADMET) polymerization of said compound by heating the compositionto a temperature of at least 30C, thereby obtaining a polymer; and crosslinking said polymer by inducing quadricyclane to norbornadiene isomerization.

[0024] In one embodiment, inducing isomerization comprises light irradiation sufficient for inducing a photothermal activation of said plasmonic material; optionally wherein said light irradiation is at a wavelength range between 200 to 1200 nm and for a time period of at least Imin.DETAILED DESCRIPTION

[0025] In some non-limiting aspects of the present invention, there is provided a photo-switchable olefin as a latent monomer. The inventors successfully exploited the to-and-fro isomerization of norbornadiene (NBD) and quadricyclane (QC) to control in situ the reactivity of monomers towards ROMP. QC is known to undergo exothermic retro-cycloaddition (RCA) reaction back to NBD. This property of QC has been utilized by the inventors to obtain latent monomers, which are labile to the ROMP catalyst and which upon activation (initiated by heat and or by photothermal response of the plasmonic material) can be switched into polymerizable NBD isomer.Latent monomer

[0026] In one aspect of the present invention, there is provided a compound represented by Formula 1:, wherein each of R1 and R2 is independently selected from H, optionally substituted alkyl, optionally substituted alkenyl, Y-R, -C(=O)OR, -C(=S)OR, -C(=NH)OR, - C(=O)NHR, -C(=S)NHR and -C(=NH)NHR, or wherein R1 and R2 are interconnected to form a4-8 membered saturated or unsaturated ring; wherein Y is a spacer; wherein R is selected from H, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted cycloalkyl, optionally substituted heterocyclyl, optionally substituted aryl, optionally substituted heteroaryl and optionally substituted alkyl-cyclyl; wherein the cyclyl is selected from cycloalkyl, heterocyclyl, aryl and heteroaryl. In some embodiments, the spacer is or comprises a heteroatom (e.g., O, N, NH, or S), -C(O)NH-, -C(O)O-, -C(O)-, -C(O)S-, -C(NH)NH-,- C(NH)O-,-C(NH)S-,5-S-, -S-C(=O), Y’-(C0-10)alkyl-X-(C0-10)alkyl-Y’, -NN-, -CNNH-, -C(=S)NH-, -C(=O)NH-O- , -C(=O)NH-NH-, -NHC(=S)-, -NHC(=O)O-, -NHC(=O)NH-, -NHC(=S)O-, -NHC(=S)NH-, -S02-, -SO-, -SO2O-, -S02NH-, -NHNH-, phosphate, phosphonate, phosphine, phosphite, including any combination thereof; wherein Y’ is a bond or a heteroatom.

[0027] In some embodiments, each of R1 and R2 is independently selected from optionally substituted C2-C15alkyl, optionally substituted C2-C15alkenyl, -C(=O)OR, -C(=S)OR, - C(=NH)OR, -C(=O)NHR, -C(=S)NHR and -C(=NH)NHR. In some embodiments, each of R1 and R2 is independently selected from optionally substituted C3-C15alkyl, optionally substituted C4- C15alkyl, optionally substituted C3-C15alkenyl, optionally substituted C4-C 15 alkenyl, C(=O)OR, -C(=S)OR, -C(=NH)OR, -C(=O)NHR, -C(=S)NHR and -C(=NH)NHR. In some embodiments, each of R1 and R2 is independently selected from -C(=O)OR, -C(=S)OR, - C(=NH)OR, -C(=O)NHR, -C(=S)NHR and -C(=NH)NHR.

[0028] In some embodiments, R is selected from optionally substituted alkyl, optionally substituted alkenyl, optionally substituted cycloalkyl, optionally substituted heterocyclyl, optionally substituted aryl, optionally substituted heteroaryl and optionally substituted alkyl- cyclyl. In some embodiments, R is selected from optionally substituted alkyl, optionally substituted cycloalkyl, optionally substituted heterocyclyl, optionally substituted aryl, optionally substituted heteroaryl and optionally substituted alkyl-cyclyl. In some embodiments, R is selected from optionally substituted alkyl, optionally substituted aryl, and optionally substituted alkyl-cyclyl.

[0029] In some embodiments, R is selected from optionally substituted (Cl-C15)alkyl, optionally substituted (Cl-ClO)alkyl, optionally substituted (C2-C10)alkyl, optionally substituted (C2- C7)alkyl, optionally substituted (C2-C15)alkenyl, optionally substituted (C2-C10) alkenyl, optionally substituted (C2-C7) alkenyl, optionally substituted (3-18, 3-14 or 3-10 membered) cycloalkyl, optionally substituted (C3-C18, C3-C14 or C3-C10) cycloalkyl optionally substituted (3-18, 3-14 or 3-10 membered)heterocyclyl, optionally substituted (6-14 membered) aryl, optionally substituted (C6-C14) aryl, optionally substituted (5-14 membered) heteroaryl and optionally substituted (C1-C15 or Cl-C10)alkyl-cyclyl. In some embodiments, the cyclyl is selected from (3-18, 3-14 or 3-10 membered)cycloalkyl, (3-18, 3-14 or 3-10 membered)heterocyclyl, (6-14 membered) aryl and (5-14 membered) heteroaryl.

[0030] In some embodiments, each of R1 and R2 is independently selected from (i) -C(=O)OR, - C(=S)OR, -C(=NH)OR, -C(=O)NHR, -C(=S)NHR and -C(=NH)NHR and (ii) -C(=O)OR; wherein R is selected from optionally substituted (Cl-C15)alkyl, optionally substituted (Cl-ClO)alkyl, optionally substituted (C2-C10)alkyl, optionally substituted (C2-C7)alkyl, optionally substituted(Cl-C15)alkenyl, optionally substituted (C2-C10) alkenyl, optionally substituted (C2-C7) alkenyl, optionally substituted (3-18, 3-14 or 3-10 membered) cycloalkyl, optionally substituted (C3-C18, C3-C14 or C3-C10) cycloalkyl optionally substituted (3-18, 3-14 or 3-10 membered)heterocyclyl, optionally substituted (6-14 membered) aryl, optionally substituted (C6-C14) aryl, optionally substituted (5-14 membered) heteroaryl and optionally substituted (Cl -Cl 5 or Cl-10)alkyl-cyclyl.

[0031] In some embodiments, each of R1 and R2 is independently selected from (i) -C(=O)OR, - C(=S)OR, -C(=NH)OR, -C(=O)NHR, -C(=S)NHR and -C(=NH)NHR and (ii) -C(=O)OR; wherein R is selected from optionally substituted (C1-C10) alkyl, optionally substituted(C6-C14) aryl, and optionally substituted (Cl -CIO) alkyl-(C6-C14) aryl.

[0032] In some embodiments, R1 and R2 represent the same or different substituents. In some embodiments, the compound is represented by Formula 1, wherein R1 and R2 are -C(=O)OR, wherein R is selected from ethyl, tert-butyl and benzyl.

[0033] In some embodiments, the compound is represented by Formula 1, wherein each of R1 and R2 is independently selected from: optionally substituted alkenyl, -C(=O)OR, -C(=S)OR, - C(=NH)OR, -C(=O)NHR, -C(=O)NRR, -C(=S)NHR -C(=S)NRR , -C(=NH)NHR and - C(=NH)NRR, or wherein R1 and R2 are interconnected to form a 4-8 membered unsaturated ring; and wherein R is optionally substituted linear, branched or cyclic alkenyl.

[0034] In some embodiments, the compound is represented by Formula 1, wherein each of R1 and R2 is independently selected from -C(=O)OR, -C(=S)OR, -C(=NH)OR, -C(=O)NHR, -C(=S)NHR and -C(=NH)NHR, or wherein R1 and R2 are interconnected to form a 4-8 membered unsaturated ring.

[0035] In some embodiments, the compound is represented by Formula 1, wherein R is optionally substituted (Cl-C15)alkenyl, optionally substituted (C2-C10) alkenyl or optionally substituted (C2-C7) alkenyl.

[0036] In some embodiments, the compound is represented by Formula 1, wherein each of R1 and R2 is -C(=O)OR or -C(=S)OR, and wherein R is optionally substituted (Cl-C15)alkenyl, optionally substituted (C2-C10) alkenyl or optionally substituted (C2-C7) alkenyl. In some embodiments, the compound is represented by Formula 1, wherein each of R1 and R2 is -C(=O)OR, and wherein R is optionally substituted (Cl-C15)alkenyl, optionally substituted (C2-C10) alkenyl or optionally substituted (C2-C7) alkenyl. In some embodiments, the compound is represented by Formula 1,wherein R is, wherein each n and m indepedntly repesents an integer between 0 and 10, or between 0 and 5, or between 0 and 7.

[0037] In some embodiments, the compound is represented by Formula 2: Formula 2A:, ein each X is independently selected from O, S, NH and NR; wherein each X is independently a bond or is selected from O, S and NH; and wherein R is an optionally substituted alkenyl. In some embodiments, the compound is represented by Formula 2 / 2A, wherein R is optionally substituted (Cl-C15)alkenyl, optionally substituted (C2-C10) alkenyl or optionally substituted (C2-C7) alkenyl.

[0038] In some embodiments, the compound is represented by Formula 2 / 2A, wherein R is

[0039] In some embodiments, the compound of the invention is characterized by chemical stability under ambient atmosphere conditions and a temperature below 30C or below 25C, wherein the chemical stability is determined by HNMR and encompasses less than 10% or less than 5% decomposition form the initial weight (or amount) of the compound. In some embodiments, the compound of the invention is characterized by chemical stability disclosed above, for a time period ranging between Id and 30d, between 1 and 60d, at least Id, at least 5d, at least lOd, including any range between.

[0040] The compound of the invention (i.e. Formulae 1 and 2) is a quadricyclane (QC). While being in the QC form the compound is devoid of double bonds and cannot be polymerized by ROMP. Accordingly, the compound of the invention represents a latent monomer or a latent ROMPprecursor. The latent monomer can be activated by inducing transformation of the QC into a norbornadiene (NBD) isomer via retro-cycloaddition (RCA). The NBD isomer or derivative of QC (according to Formula 1) has the following general structure:, wherein R1 and R2 are as described above.

[0041] In some embodiments, the compound of the invention (i.e. latent ROMP precursor) is characterized by chemical stability disclosed above and upon activation thereof is configured to undergo isomerization (or RCA) into NBD isomer. In some embodiments, the activation is a thermal activation. Thermal activation can be performed by applying heat to the latent ROMP precursor. Alternatively, the compound of the invention is in the form of a composition further comprising a plasmonic material, and wherein thermal activation is performed by photothermal activation of the plasmonic material.

[0042] In some embodiments, applying heat encompasses a temperature of at least 50, at least55, at least 60, or between 50 and 300, between 50 and 150, between 50 and 140, between 50 and 130, between 50 and 120, between 60 and 300, between 60 and 200, between 60 and 180, between 60 and 150, between 60 and 140, between 60 and 130, between 60 and 120, between 70 and 300, between 80 and 30, between 50 and 100, between 100 and 300, between 100 and 200, between 80 and 120, between 100 and 150, between 60 and 100, between 200 and 300°C, including any range between.Polymerizable composition

[0043] In another aspect of the present invention, there is provided a composition comprising a latent ring opening metathesis polymerization (ROMP) precursor and a ROMP catalyst, wherein the latent ROMP precursor is or comprises the compound(s) disclosed above.

[0044] In another aspect of the present invention, there is provided a composition comprising a latent ring opening metathesis polymerization (ROMP) precursor, a ROMP catalyst and a plasmonic material, and wherein the plasmonic material is in a form of a plurality of particles, and is characterized by a photothermal activation wavelength in a range between about 400 and about 1200 nm, including any range between. In some embodiments, each particle of the plasmonic material is or comprises a plasmonic nanoparticle encapsulated by an oxide shell.

[0045] In some embodiments, the composition of the invention is a polymerizable composition. The term “polymerizable” encompasses any (solid, liquid, flowable or solid / semi-solid) composition suitable for polymerization. The terms “composition” and “polymerizable composition” are used herein interchangeably. In some embodiments, the composition is a ready- to-use (i.e. without a need to add additional constituents prior to polymerization) polymerization precursor or polymerizable composition. In some embodiments, the composition of the invention undergoes in-situ polymerization upon activation of the latent ROMP precursor, as described herein.

[0046] In some embodiments, upon storage for at least 1 week or at least 1 month, or between Iw and 12m, between 1 w and 2m, between Iw and 6m including any range between, at a temperature below 10C, the composition is characterized by not more than 5%w / w reduction of an initial content of the latent ROMP precursor.

[0047] In some embodiments, the plasmonic material is characterized by a photothermal activation wavelength in a range between about 200 and 1200 nm, between about 200 and 400 nm, between about 400 and 900 nm, between about 400 and 1200 nm, between about 400 and 1000 nm, between 500 and 900 nm, between 600 and 900 nm, including any range between. In some embodiments, the photothermal activation wavelength corresponds to the absorbance wavelength range of the plasmonic material.

[0048] In some embodiments, the plasmonic material is in a crystalline state. In some embodiments, the plasmonic material is in a semi-crystalline state. In some embodiments, the plasmonic material is in an amorphous state. In some embodiments, the plasmonic material is in a form of plasmonic nanoparticles, each plasmonic nanoparticle is encapsulated by the oxide shell.

[0049] In some embodiments, the plasmonic nanoparticles are carbon nanoparticles (e.g., graphene, carbon nanotubes, carbon dots, carbon black, fullerenes, graphene, etc.).

[0050] In some embodiments, the plasmonic nanoparticles are metal nanoparticles. In some embodiments, the metal nanoparticles comprise or consist of a metal in a crystalline state. The term “plasmonic particles” is well understood by a skilled artisan and refers to the ability of the particles to convert light to heat via the "localized surface plasmon resonance" (LSPR) effect, plasmonic particles are capable of absorbing electromagnetic radiation and converting it into heat, resulting in a rapid and significant temperature increase under light irradiation.

[0051] In some embodiments, the metal nanoparticles are noble metal nanoparticles. In some embodiments, the metal nanoparticles consist of a noble metal (e.g. gold, silver, platinum, palladium). In some embodiments, the metal nanoparticles comprise or consist of transition metals (e.g., copper, nickel, cobalt, iron), magnetic alloys, semiconductors (e.g., titanium nitride, molybdenum disulfide, black phosphorus, other transition-metal dichalcogenides), metal oxides (e.g., Fe3O4, CuO, and defect-engineered or doped Ti Ch-based nanostructures), including any composites thereof.

[0052] In some embodiments, the plasmonic nanoparticles are isotropic particles, such as spheres and cubes. In some embodiments, the plasmonic nanoparticles are anisotropic particles including bipyramids, rods, triangular plates, prisms, stars, and chiral structures.

[0053] In some embodiments, the plasmonic nanoparticles are enclosed within a support matrix. Without being limited to any particular theory, it is postulated that the support matrix stabilizes the metal nanoparticles, preventing reorganization thereof and thus preventing formation of spherical particles, being substantially devoid of plasmonic properties.

[0054] In some embodiments, the plurality of plasmonic nanoparticles in the plasmonic material is referred to as stable, if at least 80%, at least 85%, at least 90%, at least 95%, at least 99%, by number of the plasmonic nanoparticles have a particle size between 10 and 500 nm, including any range therebetween.

[0055] In some embodiments, the support is an inert matrix encapsulating the plasmonic material (e.g., metal nanoparticles), and is devoid of reactivity towards the plasmonic material. In some embodiments, the support is a porous support. In some embodiments, the support is or comprises an oxide. In some embodiments, the oxide is selected from a metalloid oxide, and a metal oxide (e.g., titanium oxide, zirconium oxide, zinc oxide, aluminum oxide, etc.) In some embodiments, the metalloid oxide comprises silica. In some embodiments, the plasmonic material is in a form of metal nanoparticles embedded within, encapsulated within, or enclosed by an oxide material. In some embodiments, the plasmonic material is in a form of a core shell particle comprising a core consisting essentially of plasmonic metal nanoparticle, and further comprising a shell surrounding the core, wherein the shell consists essentially of porous (e.g., mesoporous) oxide material. In some embodiments, the shell of the core shell particle consists essentially of mesoporous silica. In some embodiments, the support or shell consists essentially of mesoporous silica.

[0056] In some embodiments, the plasmonic material comprises or consists essentially of a plasmonic particle (e.g. plasmonic metal particle) enclosed within an oxide shell, wherein the plasmonic material is characterized by an average particle size between 0.01 pm and 10 pm, between 1 and 200 nm, between 10 and 200 nm, between 10 and 100 nm, between 50 and 500 nm, between 10 and 500 nm, between 10 and 100 nm, between 100 and 500 nm, between 50 and 300 nm, between 10 and 500 nm, between 50 and 200 nm, between 10 and 200 nm, between 100 and 300 nm, between 300 and 500 nm, between 0.1 pm and 0.5 pm, between 0.5 pm and 10 pm, including any range between. In some embodiments, the average particle size refers to a dry particle size (e.g., as determined by SEM).

[0057] In some embodiments, the plasmonic particles are noble metal nanoparticles. In some embodiments the plasmonic particles comprise or consist essentially of Au nanoparticles. In some embodiments, the plasmonic particles comprise or consist essentially of gold nano bipyramids (AuBP). In some embodiments, the plasmonic particles comprise AuBP characterized by photothermal activation wavelength in a range between about 600 and about 1200 nm, between about 600 and about 900 nm, between 700 and 900 nm, between 750 and 900 nm, between 800 and 900 nm, between 600 and 700nm, including any range between.

[0058] In some embodiments, AuBP is AuBPeeo or AuBPsso, where 660 and 850 refers to their irradiation wavelength respectively.

[0059] Various ROMP catalysts are known in the art such as Titanacyclobutane or tantalacyclobutane complexes, alkylidene catalyst (e.g. Tungsten-carbene complexes, rutheniumcarbene complexes, and ruthenium-carbene complexes bearing NHC ligands). In some embodiments, ROMP catalyst is a Ru-complex based Grubbs-type catalyst. In some embodiments, Ru-complex is selected from Ru-carbene and Ru-alkylidene complex.

[0060] In some embodiments, the ROMP catalyst is present in the composition at an amount of between 0.1 and 50mol%, between 0.1 and 30mol%, between 0.1 and 10mol%, between 0.1 and 5mol%, between 0.1 and lmol%, between 1 and 10mol%, between 10 and 50mol%, relative to the latent ROMP precursor, relative to the latent ROMP precursor. In some embodiments, a w / w concentration of the ROMP catalyst within the composition is at least 0.01, at least 0.05, at least 0.1 at least 0.3%, at least 0.5%, at least 1%, and between 0.01 and 5%, between 0.01 and 1%, between 0.01 and 0.1, between 0.01 and 0.1%, between 0.01 and 0.5%, including any range between.

[0061] In some embodiments, a weight ratio between the plasmonic material and the latent ROMP precursor within the composition is between about 1 : 100 and 1 : 1000.000, between about 1 : 100 and 1: 100.000, between about 1: 100 and 1: 500.000, between 1: 100 and 1: 10.000, between 1: 100 and 1: 5.000, between 1:100 and 1: 1.000, between 1:1000 and 1: 10.000, between 1: 1000 and 1: 100.000, between 1: 10.000 and 1: 100.000, between 1: 100.000 and 1: 1000.000, including any range in between.

[0062] In some embodiments, a weight concentration of the plasmonic material within the composition is at least 0.0001%, at least 0.001%, at least 0.05, at least 0.01, at least 0.05, at least 0.1 at least 0.3%, at least 0.5%, at least 1%, or between 0.0001 and 0.1, between 0.001 and 0.1, between 0.01 and 0.1, between, between 0.001 and 0.05, between 0.001 and 1%, between 0.001 and 0.1%, between 0.01 and 0.1%, between 0.01 and 0.5%, between 0.01 and 0.1%, between 0. 1 and 0.5%, between 0.1 and 1%, including any range between.

[0063] In some embodiments, a w / w concentration of the latent ROMP precursor by dry weight of the composition is at least 80%, at least 90%, at least 95%, at least 93%, at least 97%, at least 98%, at least 99%, between 80 and 99.9%, between 80 and 99%, between 80 and 98%, between 80 and 97%, between 80 and 95%, between 90 and 99.9%, between 90 and 99%, between 95 and 99.9%, between 95 and 99%, including any range between.

[0064] In some embodiments, at least 80%, at least 90%, at least 95%, at least 93%, at least 97%, at least 98%, at least 99%, between 80 and 99.9%, between 80 and 99%, between 80 and 98%, between 80 and 97%, between 80 and 95%, between 90 and 99.9%, between 90 and 99%, between 95 and 99.9%, between 95 and 99% by dry weight of the composition consist of the latent ROMP precursor, the ROMP catalyst and optionally the plasmonic material. In some embodiments, the composition comprises a single latent ROMP precursor species. In some embodiments, the composition comprises two or more chemically distinct latent ROMP precursor species.

[0065] In some embodiments, the composition further comprises an organic solvent. In some embodiments, the composition comprises between 5 and 90%, between 10 and 90%, between 10 and 80%, between 10 and 50%, between 50 and 90%, between 50 and 80% of the organic solvent, by weight of the composition. In some embodiments, the organic solvent is characterized by a boiling point of at least 35 °C, at least 30 °C, at least 40 °C, at least 50 °C, at least 70 °C, at least 90 °C, including any range between.

[0066] In some embodiments, the organic solvent is suitable for substantially dissolving the latent ROMP monomer. In some embodiments, a solubility of the latent ROMP monomer within the organic solvent is at least O.lg / L, at least Ig / L, at least 5g / L, at least lOg / L, at least 50g / L, at least lOOg / L, including any range between. In some embodiments, the composition is a liquid, wherein the entire constituents are dissolved in the organic solvent. In some embodiments, the composition is a solution. In some embodiments, the composition is a solution of the latent ROMP monomer.

[0067] In some embodiments, the composition is shapeable. In some embodiments, the shapeable composition encompasses a flexible, elastic, and / or deformable material capable for obtaining a predetermined shape. In some embodiments, the shapeable composition is capable for obtaining a predetermined shape and to further retaining the predetermined shape without applying additional force (i.e., plastic deformation). In some embodiments, the shapeable composition is capable for obtaining a predetermined shape at a temperature above glass transition point / melting temperature of the composition. In some embodiments, the shapeable composition capable for obtaining a predetermined shape at a temperature between 0 and 60°C, between 10 and 60°C, between 10 and 50°C, between 10 and 40°C, between 10 and 30°C, including any range between.

[0068] In some embodiments, the composition is in a liquid state, or in a semi-liquid state at a temperature between 0 and 50°C, between 0 and 40°C, between 0 and 30°C, between 10 and 30°C, including any range between. In some embodiments, the composition is a homogenous composition devoid of phase separation.

[0069] In some embodiments, the composition is flowable. In some embodiments, the composition is shapeable by injection, casting or molding (e.g., cast molding, injection molding).

[0070] In another aspect, the composition is in a form of a composite comprising the ROMP catalyst, the latent ROMP precursor and a polymer.

[0071] In another aspect, there is a composite comprising the ROMP catalyst, a polymer derived from the latent ROMP precursor of Formula 2. In some embodiments, the polymer derived from the latent ROMP precursor of Formula 2 is a cross-linkable polymer. In some embodiments, the cross-linkable polymer is obtained by ADMET polymerization of the latent ROMP precursor of Formula 2 in the presence of the ADMET catalyst. In some embodiments, the ROMP catalyst in the composite is suitable for inducing ROM or ADMET polymerization. In some embodiments, the composite further comprises the latent ROMP precursor of Formula 2 (i.e. unreacted precursor composing up to 50%, or up to 30%, up to 20% by weight relative to the cross-linkable polymer).

[0072] In some embodiments, a w / w concentration of the cross-linkable polymer by dry weight of the composite is at least at least 50%, at least 60%, at least 70%, between 50 and 90%, between 50 and 80%, between 80 and 97%, between 80 and 95%, between 90 and 99.9%, between 90 and 99%, between 95 and 99.9%, between 95 and 99%, including any range between.

[0073] In some embodiments, the cross-linkable polymer is represented by Formula 3:as described above; wherein n is an integer being between 1 and 8, and wherein m represents an integer being between 100 and 100000. In some embodiments, the cross-linkable polymer is represented by Formula 3, wherein each of X and XI is independently selected from O, S and NH. In some embodiments, the cross-linkable polymer is represented by Formula 3, wherein each of X and XI is O.

[0074] In some embodiments, the cross-linkable polymer has an average molecular weight (Mw) between 10.000 and 1.000.000 Da, between 10.000 and 500.000 Da, between 10.000 and 300.000 Da, between 10.000 and 200.000 Da, including any range between, wherein Mw is determined by SEC. In some embodiments, the cross-linkable polymer has a polydispersity index (determined by SEC) between 1.1 and 1.6, between 1.3 and 1.6 or between 1.3 and 1.5, including any range between.

[0075] In another aspect, there is provided a crosslinked polymer derived from the cross-linkable polymer, wherein derived is by inducing ROMP polymerization of the cross-linkable polymer. In some embodiments, ROMP polymerization of the cross-linkable polymer is by activating (i.e. via thermal activation disclosed above) of the cross-linkable polymer in the presence of ROMP catalyst. In some embodiments, the crosslinked polymer is represented by Formula 4:and m are as described herein and wherein k represents an integer being between 100 and 100000.

[0076] In some embodiments, the crosslinked polymer is represented by Formula 4, wherein each of X and XI is independently selected from O, S and NH. In some embodiments, the crosslinked polymer is represented by Formula 4, wherein each of X and XI is O.

[0077] In some embodiments, the crosslinked polymer has an average molecular weight (Mw) between 10.000 and 1.000.000 Da, between 10.000 and 500.000 Da, between 10.000 and 300.000 Da, between 10.000 and 200.000 Da, including any range between, wherein Mw is determined by SEC. In some embodiments, the crosslinked polymer has a polydispersity index (determined by SEC) between 1.1 and 1.6, between 1.3 and 1.6 or between 1.3 and 1.5, including any range between. In some embodiments, the crosslinked polymer has at least 10 fold reduced solubility in an organic solvent, compared to the solubility of the corresponding cross-linkable polymer.

[0078] In some embodiments, the composite further comprises the plasmonic material. In some embodiments, the ROMP catalyst is present in the composite at an amount of between 0.1 and 50mol%, between 0.1 and 30mol%, between 0.1 and 10mol%, between 0.1 and 5mol%, between 0.1 and lmol%, between 1 and 10mol%, between 10 and 50mol%, relative to the latent ROMP precursor, including any range between. In some embodiments, a w / w concentration of the ROMP catalyst within the composite is at least 0.01, at least 0.05, at least 0.1 at least 0.3%, at least 0.5%, at least 1%, and between 0.01 and 5%, between 0.01 and 1%, between 0.01 and 0.1, between 0.01 and 0.1%, between 0.01 and 0.5%, including any range between.

[0079] In some embodiments, a weight ratio between the plasmonic material and the latent ROMP precursor within the composite is between about 1: 100 and 1:1000.000, between about 1: 100 and 1: 100.000, between about 1: 100 and 1: 500.000, between 1: 100 and 1: 10.000, between 1: 100 and 1: 5.000, between 1:100 and 1: 1.000, between 1:1000 and 1: 10.000, between 1: 1000 and 1:100.000, between 1: 10.000 and 1: 100.000, between 1: 100.000 and 1: 1000.000, including any range in between.

[0080] In some embodiments, a weight concentration of the plasmonic material within the composite is at least 0.0001%, at least 0.001%, at least 0.05, at least 0.01, at least 0.05, at least 0.1 at least 0.3%, at least 0.5%, at least 1%, or between 0.0001 and 0.1, between 0.001 and 0.1, between 0.01 and 0.1, between, between 0.001 and 0.05, between 0.001 and 1%, between 0.001 and 0.1%, between 0.01 and 0.1%, between 0.01 and 0.5%, between 0.01 and 0.1%, between 0. 1 and 0.5%, between 0.1 and 1%, including any range between.

[0081] In some embodiments, a w / w concentration of the latent ROMP precursor by dry weight of the composite is at least 10%, at least 20%, at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, between 10 and 80%, between 10 and 50%, between 50 and 80%, between 80 and 97%, between 80 and 95%, between 90 and 99.9%, between 90 and 99%, between 95 and 99.9%, between 95 and 99%, including any range between.

[0082] In some embodiments, a w / w concentration of the polymer by dry weight of the composite is at least at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, between 30 and 90%, between 30 and 50%, between 50 and 80%, between 80 and 97%, between 80 and 95%, between 90 and 99.9%, between 90 and 99%, between 95 and 99.9%, between 95 and 99%, including any range between.

[0083] In some embodiments, between 80 and 100%, between 80 and 99%, between 80 and 95%, between 90 and 100%, between 95 and 99%, or between 95 and 97% by dry weight of the composite consists, or consist essentially of the polymer, the ROMP catalyst, the latent ROMP precursor, and optionally of the plasmonic material.

[0084] In some embodiments, the polymer is a thermoplastic polymer. In some embodiments, the polymer is a thermoset polymer. In some embodiments, the polymer is an olefin metathesis polymer (e.g. a polymer obtained via metathesis polymerization, such as by ROMP or ADMET). In some embodiments, the polymer is a ROM polymer. In some embodiments, the polymer is a thermoplastic ROM polymer.

[0085] In some embodiments, the ROM polymer is selected from: polycyclopentene, polycyclobutene, polycycloheptene, polycyclooctene, polydicyclopentadiene, polynorbornene, polynorbornadiene, including any derivative, any copolymer or any combination thereof. In some embodiments, ROM polymer is polycyclooctene.

[0086] In some embodiments, the composite is a solid or a semi-solid at a temperature below 30C, or below 25C. In some embodiments, the polymer is in a form of a continuous matrix within the composite of the invention. In some embodiments, the ROMP catalyst and optionally the plasmonic material is embedded and / or homogenously distributed within the polymeric matrix. In some embodiments, the particles of the plasmonic material are physisorbed and / or chemisorbed on or within the polymeric matrix.

[0087] As used herein, the term “matrix” refers to a 3-dimensional structure formed by polymeric chains that are randomly, and / or under certain order or control, distributed therewithin. Matrix may further include any materials incorporated within and / or interposed between the polymeric chains. In some embodiments, the matrix comprises randomly oriented polymeric chains. In some embodiments, each polymeric chain within the matrix is in contact with at least one additional polymeric chain. In some embodiments, the polymeric chains are randomly distributed within the matrix, to obtain a three-dimensional mesh structure comprising a void space between the chains. In some embodiments, the polymeric chains are randomly distributed within the matrix thus forming a plurality of pores (or void space). In some embodiments, the polymeric matrix is an intertwined matrix composed of randomly distributed polymeric chains, the plasmonic material, the ROMP catalyst and the latent ROPM precursor. In some embodiments, the term “bound” refers to any non-covalent bond or interaction, such as electrostatic bond, dipole-dipole interaction, Van- der-walls’ interaction, ionotropic interaction, hydrogen bond, hydrophobic interactions, pi-pi stacking, London forces, etc. In some embodiments, the non-covalent bond or interaction is a stable bond or interaction, wherein stable is as described herein.

[0088] The term “composite”, as used herein, refers to a substantially uniform material which cannot be easily separated into individual constituents (e.g., the plasmonic material, the ROMP catalyst and the polymer / latent ROMP precursor). In some embodiments, the composite is substantially devoid of phase separation or disintegration (also referred to herein as “stable” composite).

[0089] In some embodiments, the composite of the invention is polymerizable, to obtain a ROM- copolymer comprising a first block and a second block, wherein the first block is or comprises the polymer and the second block is derived from the latent ROMP precursor. In some embodiments, the second block is or comprises a polymerized NBD isomer of the latent ROMP precursor.

[0090] In some embodiments, the composite of the invention is polymerizable, to obtain a ROM polymer comprising a first polymer crosslinked by a second polymer, wherein the first polymer is or comprises the polymer disclosed above, and the second polymer is derived from the latent ROMP precursor.

[0091] In some embodiments, the composite or composition of the invention is a plasmonic composite configured to emit thermal radiation upon light irradiation at the photothermal activation wavelength. In some embodiments, the thermal radiation emitted by the plasmonic composite comprises a temperature increase of the plasmonic composite by at least 10°C, at least 20°C, at least 30°C, at least 50°C, at least 100°C, at least 150°C, at least 200°C, up to about 500°C, up to about 300°C, up to about 200°C, up to about 150°C, up to about 100°C, including any range between. The temperature increase of the material is determined based on a temperature of the same material before irradiation. In some embodiments, the plasmonic composite upon a plurality of repetitive photothermal activation and relaxation cycles retains at least 90%, at least 85%, at least 80%, at least 75%, at least 70%, and between 70 and 90%, between 70 and 80%, between 75 and 85%, between 80 and 90% of the initial thermal energy. In some embodiments, the plurality of repetitive photothermal activation and relaxation cycles comprises at least 50 cycles and between 50 and 150, between 50 and 80, between 80 and 100, between 90 and 110, between 95 and 120, between 125 and 150 cycles, including any range in between.

[0092] As used herein, the term “substantially” refers to at least 85%, at least 90%, at least 92%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or between 60 and 99.9%, between 70 and 80%, between 70 and 90%, between 80 and 90%, between 90 and 95%, between 95 and 99.9%, including any range or value therebetween.

[0093] In another aspect, there is provided an article comprising the composition or the composite of the invention. In some embodiments, the article is a thermally / photothermally activated polymer precursor. In some embodiments, the article is obtained by shaping the composite. In some embodiments, the article is a mold shaped article.

[0094] In some embodiments, the article is in a form of a film. In some embodiments, the film is a mono-layer. In some embodiments, the film is a multilayer. In some embodiments, the film layer, is in a form of a continuous layer. In some embodiments, the article is in a form of pellets. In some embodiments, the article is in a form of a filament.

[0095] In some embodiments, the article is 3D printing composition or a 3D printing resin. In some embodiments, the article is for use in conventional 3D printing methods, such as Fused Deposition Modeling (FDM) utilizing solid thermoplastic filaments that are melted and extruded through a heated nozzle; Stereolithography (SLA), Digital Light Processing (DLP) or PolyJet / MultiJet Printing (MJP) utilizing liquid resins or inks that are cured or solidified during the printing process. Methods

[0096] In another aspect, there is provided a method for synthesizing a ROM polymer, comprising subjecting the polymerizable composition to conditions suitable for activation of the latent ROMP precursor to induce isomerization to a norbornadiene isomer and subsequently or simultaneously inducing ROMP of the norbornadiene isomer; wherein the conditions comprise thermal activation.

[0097] In some embodiments, thermal activation comprises subjecting the polymerizable composition to a temperature of at least 50, at least55, at least 60, or between 50 and 300, between 50 and 150, between 50 and 140, between 50 and 130, between 50 and 120, between 60 and 300, between 60 and 200, between 60 and 180, between 60 and 150, between 60 and 140, between 60 and 130, between 60 and 120, between 70 and 300, between 80 and 30, between 50 and 100, between 100 and 300, between 100 and 200, between 80 and 120, between 100 and 150, between 60 and 100, between 200 and 300°C, including any range between; and for a time period of at least one minute(m), at least 0.1m, at least 3m, at least 10m, at least 20m, at least 30m, at least 60m, at least 5hours, at least lOhours, between 5 min and 2h, between 5 min and 3h, between 5min and Ih, including any range between. In some embodiments, the conditions further comprise mixing the polymerizable composition and / or applying ultrasonic waves. In some embodiments, thermal activation is by heating.

[0098] In some embodiments, the polymerizable composition further comprises the plasmonic material, wherein the thermal activation is selected from (i) heating and (ii) photothermal activation by light irradiating the polymerizable composition at a wavelength or at a wavelength range appropriate for inducing photothermal response of the plasmonic material, or both (i) and (ii). In some embodiments, photothermal activation comprises light irradiation at a radiation dose sufficient for activating the latent ROMP monomer to induce NBD isomerization of at least 20%, at least 30%, at least 50%, at least 70%, at least 90%, or between 20 and 99% of the initial amount of the latent ROMP monomer (as determined by HNMR).

[0099] In some embodiments, the wavelength or the wavelength range appropriate for photothermal activation as described hereinabove (i.e. between 400 and 1200 nm).

[0100] In some embodiments, photothermal activation comprises light irradiating the polymerizable composition at a wavelength and at a radiation dose sufficient for initiating a photothermal response of the plasmonic material, thereby activating the latent ROMP monomer. In some embodiments, the radiation dose is sufficient for providing the polymerizable composition to a temperature of at least 50, at least55, at least 60, or between 50 and 300, between 50 and 150, between 50 and 140, between 50 and 130, between 50 and 120, between 60 and 300, between 60 and 200, between 60 and 180, between 60 and 150, between 60 and 140, between 60 and 130, between 60 and 120, between 70 and 300, between 80 and 30, between 50 and 100, between 100 and 300, between 100 and 200, between 80 and 120, between 100 and 150, between 60 and 100, between 200 and 300°C, including any range between. In some embodiments, photothermal activation comprises light irradiating the polymerizable composition for a time period of at least one minute(m), at least 0.1m, at least 3m, at least 10m, at least 20m, at least 30m, at least 60m, at least 5hours, at least lOhours, including any range between.

[0101] In some embodiments, the method is performed in the organic solvent. In some embodiments, the composition is a liquid composition (e.g. a solution). In some embodiments, the composition is a liquid composition substantially devoid of the organic solvent (i.e. not more than 5%, 1% or 0.1% of the organic solvent by volume of the composition).

[0102] In some embodiments, the polymerizable composition comprises a w / w ratio between the plasmonic material and the latent ROMP monomer between 1: 10 and 1:1.000.000, between 1: 10 and 1: 100, between 1:1 and 1:100, between 1: 10 and 1:50, between 1:50 and 1: 1000, between 1:50 and 1: 10,000, between 1: 100 and 1:1000, between 1:100 and 1:10,000, between about 1: 10 and 1:100.000, between about 1:50 and 1: 100.000, between about 1:100 and 1: 1.000.000, between about 1:1000 and 1: 100.000, between about 1: 1000 and 1: 1.000.000, between about 1:100 and 1: 500.000, between about 1:100 and 1: 100.000, between 1: 100 and 1: 10.000, between 1:100 and 1: 5.000, between 1:100 and 1: 1.000, including any range in between.

[0103] In some embodiments, w / w a concentration of the latent ROMP precursor in the polymerizable composition is between 50 and 99%, including any range between. In some embodiments, the polymerizable composition is a solution, wherein a concentration of the latent ROMP precursor in the polymerizable composition is between 0.5 and 10M, between 0.5 and 5M,between 0.5 and 5M, between 0.5 and IM, between 1 and 5M, between 5 and 10M, including any range between.

[0104] In some embodiments, a concentration of the ROMP catalyst within the polymerizable composition is at least 0.05%, at least 0.1%, at least 0.5%, at least 1%, or between 0.1 and 5%, between 0.1 and 2%, between 0.1 and 1%, between 0.05 and 5%, between 0.05 and 1%, between 0.05 and 0.5%, between 0.1 and 5%, between 0.1 and 1%, between 0.1 and 0.5%, including any range between. In some embodiments, a concentration of the ROMP catalyst, within the polymerizable composition is at least 0.5mol%, at least lmol%, or between 0.1 and 20mol%, between 0.1 and 2 mol %, between 0.1 and 1 mol %, between 0.05 and 5 mol %, between 0.05 and 1 mol %, between 0.05 and 0.5 mol %, between 0.1 and 5 mol %, between 0.1 and 1 mol %, between 1 and 5 mol %, including any range between.

[0105] In some embodiments, a concentration of the plasmonic material within the polymerizable composition is at least 10 ppm, at least 50 ppm, between 10 ppm and 0.1%w / w, between 10 ppm and lOOOppm, between 10 ppm and 500ppm, between 50 ppm and lOOppm, between 100 ppm and lOOOppm, between 100 ppm and 0.5%, between 100 ppm and l%w / w, including any range between.

[0106] In some embodiments, the method further comprises shaping the polymerizable composition, thereby obtaining a shaped article; wherein shaping is performed prior to performing thermal activation. In some embodiments, shaping comprises molding, 3D printing or casting. In some embodiments, shaping is for manufacturing the article disclosed herein.

[0107] In some embodiments, the method is for synthesizing a ROM polymer. In some embodiments, the ROM polymer is a ROM block co-polymer comprising a first block derived from a first latent ROMP precursor and a second block derived from a second latent ROMP precursor, the method comprises performing thermal activation of a first polymerizable composition comprising the first latent ROMP precursor (together with the ROMP catalyst and optionally the plasmonic material) to obtain a first block; contacting the first block with a second polymerizable composition comprising the second latent ROMP precursor (together with the ROMP catalyst and optionally the plasmonic material) to obtain a mixture, and performing thermal activation of the mixture, wherein the thermal activation is as described herein.

[0108] In some embodiments, the ROM polymer is a ROM block co-polymer comprising a first comprising an olefin metathesis polymer and a second block comprising the ROM polymer derivedfrom the latent ROMP precursor, the method comprises inducing ROMP polymerization by contacting a precursor of the olefin metathesis polymer with an olefin metathesis catalyst and optionally heating the to a temperature disclosed hereinabove, to obtain a first block; contacting the first block with the polymerizable composition comprising the latent ROMP precursor (together with the ROMP catalyst and optionally the plasmonic material) to obtain a mixture, and performing thermal activation of the mixture, wherein the thermal activation is as described herein.

[0109] In some embodiments, the ROM polymer is a ROM block co-polymer comprising a first comprising an olefin metathesis polymer and a second block comprising the ROM polymer derived from the latent ROMP precursor, the method comprises inducing ROMP polymerization by contacting a precursor of the olefin metathesis polymer with an olefin metathesis catalyst and optionally heating the to a temperature disclosed hereinabove, to obtain a first block; contacting the first block with the polymerizable composition comprising the latent ROMP precursor (together with the ROMP catalyst and optionally the plasmonic material) to obtain a mixture, and performing thermal activation of the mixture, wherein the thermal activation is as described herein.

[0110] In some embodiments, the precursor of the olefin metathesis polymer is a cycloalkene. In some embodiments, the cycloalkene is compatible with ROM polymerization. In some embodiments, the cycloalkene is capable of undergoing polymerization so as to form a ROM polymer under conditions suitable for ROM polymerization (e.g., a ROMP catalyst and by providing sufficient activation energy such as by heating the reaction mixture to a suitable temperature).

[0111] Exemplary cycloalkenes include but are not limited to cyclopentene, cyclobutene, cycloheptene, cyclooctene, dicyclopentadiene, norbornene, norbornadiene, including any derivative thereof. In some embodiments, the first block is selected from polycyclobutene, polycycloheptene, polycyclooctene, polydicyclopentadiene, polynorbornene, polynorbornadiene, including any copolymer or any combination thereof. In some embodiments, the cycloalkene is cyclooctene and the first block is polycyclooctene.

[0112] In some embodiments, the ROM polymer of the invention is characterized by an average molecular weight (Mw) between 50.000 and 10.000.000 Da, between 50.000 and 200.000 Da, between 100.000 and 1.000.000 Da, between 100.000 and 500.000 Da, including any range between as determined by SEC.

[0113] In some embodiments, the ROM polymer of the invention is characterized by a PDI of between 1.0 and 1.8, between 1.1 and 1.5, between 1.1 and 1.6, between 1.1 and 1.3 including any range between, as determined by SEC. In some embodiments, the ROM polymer of the invention is characterized by Mw and by PDI as disclosed hereinabove.

[0114] In some embodiments, the ROM polymer comprises trace amounts (e.g. between 1 and lOOppm) of the latent ROMP polymer precursor. In some embodiments, the ROM polymer comprises the plasmonic material and optionally trace amounts (e.g. between 1 and lOOppm) of the latent ROMP polymer precursor.

[0115] In another aspect, there is provided a method for synthesizing the crosslinked polymer disclosed above, the method comprises providing the polymerizable composition comprising the latent ROMP precursor of Formula 2 (together with the ROMP catalyst and optionally the plasmonic material, as disclosed above); inducing ADMET polymerization of the latent ROMP precursor, thereby obtaining the cross-linkable polymer; and crosslinking the cross-linkable polymer by thermal activation of the latent ROMP precursor to induce isomerization of the latent ROMP precursor to a norbornadiene isomer thereof and to further induce ROM polymerization of the norbornadiene isomer.

[0116] In some embodiments, ADMET polymerization is induced by heating the composition to a temperature of at least 30°C, at least 35°C, at least 40°C, between 30 and 50°C, between 25 and 50°C, between 30 and 50°C, between 30 and 45°C, between 35 and 50°C, between 35 and 45°C, between 25 and 30°C, between 30 and 40°C, between 40 and 50°C, between 25 and 45°C, including any range between.

[0117] In some embodiments, thermal activation comprises thermal heating and / or photothermal activation by light irradiation (if the polymerizable composition comprises the plasmonic material), as disclosed above.

[0118] In some embodiments, the step of inducing ADMET polymerization results in a shapeable composition. In some embodiments, the method further comprises shaping the shapeable composition (e.g. by 3D printing, or any other method such as disclosed above) to obtain a shaped composition; and subsequently crosslinking the shaped composition as disclosed above (also used herein as “curing").

[0119] In some embodiments, the shapeable composition is a thermoplastic composition, and curing is performed to obtain a thermoset polymer (i.e. the crosslinked polymer). In someembodiments, curing is performed by photothermal activation via light irradiation, as disclosed above. A skilled artisan will appreciate that the light radiation dose may be varied so as to modify the crosslinking degree of the resulting crosslinked polymer.

[0120] In some embodiments, the method of the invention is performed in one-pot. In some embodiments, the term “one pot” is meant to refer to a process wherein the entire steps of the process are carried out in a single reaction vessel, typically, but not exclusively, without removing therefrom any intermediate products.General:

[0121] As used herein the terms “about” or "approximately" refer to ± 10 %.

[0122] The terms "comprises", "comprising", "includes", "including", “having” and their conjugates mean "including but not limited to".

[0123] The term “consisting of means “including and limited to”.

[0124] The term "consisting essentially of" means that the composition, method or structure may include additional ingredients, steps and / or parts, but only if the additional ingredients, steps and / or parts do not materially alter the basic and novel characteristics of the claimed composition, method or structure.

[0125] The word “exemplary” is used herein to mean “serving as an example, instance or illustration”. Any embodiment described as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments and / or to exclude the incorporation of features from other embodiments.

[0126] The word “optionally” is used herein to mean “is provided in some embodiments and not provided in other embodiments”. Any particular embodiment of the invention may include a plurality of “optional” features unless such features conflict.

[0127] As used herein, the singular form "a", "an" and "the" include plural references unless the context clearly dictates otherwise. For example, the term "a compound" or "at least one compound" may include a plurality of compounds, including mixtures thereof.

[0128] As used herein, the term “substituted” or the term “substituent” are related to one or more (e.g., 2, 3, 4, 5, or 6) substituents, wherein the substituent(s) is as described herein. As used herein, the term substituent comprises halogen, amino, oxo, thioxo, halo, -C(=O)R’, -NO2, -CN, -OH, - CONH2, -CONR’2, -CNNR’2, -CSNR’2, -CONH-OH, -CONH-NH2, -NHCOR, -NHCSR, - NHCNR, -NC(=O)OR, -NC(=O)NR’, -NC(=S)OR’, -NC(=S)NR’, -SO2R’, -SOR’, -SR’, -S020R’, -SO2N(R’)2, -NHNR’2, -NNR’, C1-C6 haloalkyl, optionally substituted C1-C6 alkyl, - NH2, -NH(C1-C6 alkyl), -N(C1-C6 alkyl)2, C1-C6 alkoxy, C1-C6 haloalkoxy, hydroxy(Cl-C6 alkyl), hydroxy(Cl-C6 alkoxy), alkoxy(Cl-C6 alkyl), alkoxy(Cl-C6 alkoxy), C1-C6 alkyl-NR’2, C1-C6 alkyl-SR’, -CONH(C1-C6 alkyl), -CON(C1-C6 alkyl)2, -C02H, -C02R’, -OCOR, - OCOR’, -OC(=O)OR’, -OC(=O)NR’, -OC(=S)OR’, -OC(=S)NR’, or a combination thereof; wherein each R’ independently represents hydrogen, or is selected from the group comprising optionally substituted C1-C10 alkyl, optionally substituted C3-C10 cycloalkyl, optionally substituted C3-C10 heterocyclyl, optionally substituted heteroaryl, optionally substituted aryl, or a combination thereof.

[0129] Throughout this application, various embodiments of this invention may be presented in a range format. It should be understood that the description in range format is merely for convenience and brevity and should not be construed as an inflexible limitation on the scope of the invention. Accordingly, the description of a range should be considered to have specifically disclosed all the possible subranges as well as individual numerical values within that range. For example, description of a range such as from 1 to 6 should be considered to have specifically disclosed subranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6 etc., as well as individual numbers within that range, for example, 1, 2, 3, 4, 5, and 6. This applies regardless of the breadth of the range.

[0130] Whenever a numerical range is indicated herein, it is meant to include any cited numeral (fractional or integral) within the indicated range. The phrases “ranging / ranges between” a first indicate number and a second indicate number and “ranging / ranges from” a first indicate number “to” a second indicate number are used herein interchangeably and are meant to include the first and second indicated numbers and all the fractional and integral numerals therebetween.

[0131] As used herein the term "method" refers to manners, means, techniques and procedures for accomplishing a given task including, but not limited to, those manners, means, techniques and procedures either known to, or readily developed from known manners, means, techniques and procedures by practitioners of the chemical, pharmacological, biological, biochemical and medical arts.

[0132] It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention, which are, for brevity, described in the context of asingle embodiment, may also be provided separately or in any suitable subcombination or as suitable in any other described embodiment of the invention. Certain features described in the context of various embodiments are not to be considered essential features of those embodiments, unless the embodiment is inoperative without those elements.

[0133] Various embodiments and aspects of the present invention as delineated hereinabove and as claimed in the claims section below find experimental support in the following examples.EXAMPLES

[0134] Reference is now made to the following examples which, together with the above descriptions, illustrate the invention in a non-limiting fashion.

[0135] Presented herein is a monomer-focused, controlled polymerization system with the aim of expanding the current outlook beyond the traditional design of catalysts. The metathesis inactive QC species were produced in quantitative yields resulting in extremely stable formulations in the presence of highly active metathesis catalysts. The RCA reaction reverting to NBD was of gold bipyramids at different wavelengths. The photothermal approach was shown to activate the monomers more efficiently leading to improved polymerization kinetics and yields. Furthermore, the monomers’ latency was exploited to develop, on the one hand, a one -pot block copolymer synthesis and, on the other, a sequential crosslinking mechanism. These in situ processes comprise accomplishments unattainable by state-of-the-art metathesis reactions using latent / conventional catalysts. Finally, by masking the light source driving the photothermal polymerization of the latent monomer, we also achieved spatial control, which is highly significant for example in 3D-printing applications.Materials

[0136] All materials were purchased from Sigma-Aldrich unless noted otherwise. Ultrapure water (type 1, 18.2 M ) from Millipore® Direct-Q® 3 with UV was used. Cetyltrimethylammonium chloride (CTAC) sodium borohydride ReagentPlus 99 %, sodium citrate tribasic BioUltra > 99.5 %, gold chloride trihydrate 99.9 %, cetyltrimethylammonium bromide (CTAB) > 99 %, ascorbic acid BioXtra > 99.0 %, hydrochloric acid 32 %, silver nitrate BioXtra > 99 %, tetraethyl orthosilicate (TEOS) reagent grade 98 %, ammonium hydroxide 28 % in water 99.9 %, benzyl bromide 99 % was purchased from Alfa Aesar (Thermo Scientific), 5 -bromo-pentene 95 % was purchased from Aaron Chemical, tert-butyl bromide > 98 %, was purchased Alfa Aesar (ThermoScientific), but-2-ynedioic acid 95 % was purchased from Aaron Chemical, diethyl acetylenedicarboxylate 96 % was purchased from Alfa Aesar (Thermo Scientific), 1, 2,3,4- tetramethylcyclopenta-l,3-diene 85 % was purchased from Alfa Aesar (Thermo Scientific), dicyclopentadiene 93 %, Hoveyda-Grubbs 2ndgeneration 97 % (HG-II, Umicore M720) and Ultra LatMet (bis-CAAC, AS2098) was kindly provided by Apeiron synthesis.Methods

[0137] Synthesis of NBD derivatives. NBDi was synthesized as follows: freshly distilled cyclopentadiene (1.3 eq) was added dropwise to cold diethyl acetylene-dicarboxylate (1 eq) and the mixture was stirred under cooling and neat conditions for 4 hours. The solution was concentrated on a rotary evaporator, and the residue was distilled under reduced pressure to afford a colorless oil. Typical syntheses yielded between 1-3 grams of product. NBD2 was synthesized in two steps. The first step based on reference 45 was the Diels-Alder reaction of but-2-ynedioic acid and cyclopentadiene. Initially, But-2-ynedioic acid (1 eq) was dissolved in water, and cyclopentadiene ( 1 eq) was added. Then the solution was stirred for 30 minutes at room temperature and a yellow solid was obtained and washed with hexane. The second step, modified from reference 40, was a substitution under basic conditions. A mixture of 2,5-norbornadiene-2,3-dicarboxylic acid dissolved in N, N-dimethylacetamide and K2CO3 (6 eq) was stirred for an hour at room temperature. Then, benzyl bromide (2.2 eq) was added, and the reaction was stirred for 18 hours at room temperature. The reaction was quenched with IM HC1 solution and extracted 3 times with diethyl ether. The combined organic phase was dried using anhydrous sodium sulfate, filtered and concentrated on a rotary evaporator. The residue was purified by silica-gel column chromatography affording a white solid. Typical syntheses yielded between 1-3 grams of product. NBD3 was synthesized as NBD2 exchanging benzyl bromide with tert-butyl bromide (3 eq) and stirring the reaction for 48 hours at 70 °C (yield 10%). NBD4 was synthesized as NBD2. 5 -bromopent- l-ene was used (2.2 eq) instead of benzyl bromide, and the reaction was mixed for 48 hours at 60 °C (yield 42%). NBDtet was synthesized according to the same procedure as NBDi with 1, 2,3,4- tetramethylcyclopenta-l,3-diene instead of cyclopentadiene (yield 91%).

[0138] UV photoisomerization of NBD to QC. The preparative photoisomerizations were carried out by placing a quartz cuvette with the corresponding material in a Luzchem-LZC photoreactor and irradiated 313 nm light until full conversion (times depend on total reaction volume). NBD2, 3were dissolved in a minimal amount of DCM. Typical experiments were carried out on a 1-4 g scale requiring up to 72 hours to fully convert to QC.

[0139] Synthesis of silica encapsulated AuBPs. Gold bipyramids were prepared and then encapsulated as follows: gold bipyramids were synthesized by the addition of gold chloride (5 ml, 10 mM), HC1 (2 ml, 1 M), AgNCh (1 ml, 10 mM) and ascorbic acid (0.8 ml, 100 mM) to a solution of cetyl trimethylammonium bromide (CT AB) (100 ml, 100 mM). Then injection of a seed solution (60 pl as prepared), previously prepared by rapidly reducing gold chloride with NaBFL in a solution of CTAC and sodium citrate. Finally, the reaction is stirred at 30 °C for 2 hours. Mesoporous silica encapsulation was achieved by adding NaOH (30 pl, 0.1 M) and tetraethylorthosilicate (TEOS) (10 pl) to a CTAB (10 ml, 0.3 mM) solution of AuBPs (2 OD) and shaking overnight at 30 °C. Stober encapsulation was performed directly after the first encapsulation. Aqueous ammonia (250 pl, 28%) and TEOS (25 pl, 20% in ethanol) were added to an ethanol solution of AuBPs (10 ml, 4 OD). The reaction was left overnight in a shaker at 120 rpm and 30 °C. Finally, encapsulated AuBPs were washed 3 times with ethanol and concentrated for use.

[0140] Catalyst sensitivity and reaction conditions. All reactions unless specified otherwise were carried out in a closed 4 ml vial without stirring. No special measures such as eliminating moisture from vials and solvents or using an inert atmosphere, were taken while carrying out reactions. As shown in Fig. 5d the catalyst is stable in the presence of the monomers with slow gradual degradation beginning to occur after approximately four weeks at 4 °C. Regarding the functional group tolerance of the initiators used, the ester group is the only functional group in the explored monomers. Esters are very common functional groups in olefin metathesis substrates and monomers; present even in the most popular bench-mark reactions (e.g., RCM of diethyl dially Imalonate), therefore, we do not believe our work provides new insights in this matter.

[0141] Photothermal reaction procedure. Photothermal reactions were irradiated with the corresponding wavelength (850 nm for AuBPsso and 660 nm for AuBPeeo) to the set temperature. The temperature was then maintained by a LabView program controlling a feedback loop between the thermometer and LED, switching on illumination whenever temperature decreased below the set value.

[0142] Polymerization of QC. Formulations were prepared by dissolving the desired amount of AuBPs into QC (typically 200 pl which corresponds to 236 and 247 mg for QCi and QC2 accordingly). Catalyst was added accordingly by first dissolving in a minimal amount of DCM(normally 30 l) and then mixing to obtain the final formulation of QC / AuBP / catalyst. The formulation was then heated either by PTH or CHeat and polymerization was monitored by NMR. Formulations used for investigating the interaction of latent monomer and catalyst, and formulation stability were prepared as described here. When using Ru-diiodo and RuCE, THF and acetone were used instead of DCM, respectively.

[0143] Di-block copolymer synthesis. Initially, AuBPsso (5 OD) were dissolved into a mixture of QC2 and NBDi (2: 1 molar ratio corresponding to 1 mmol or 360 mg of QC2 and 0.5 mmol or 118 mg of NBDi). Next, HG-II (1 mol% relative to QC2 i.e., 6.2 mg) was dissolved with a minimal amount of DCM (30 pL) and added to the mixture. The mixture was then quickly stirred using a vortex to enable homogeneous dispersion of the catalyst before the solution became too viscous. After 10 minutes the viscous mixture was heated with PTH (850 nm) to 80 °C for 20 minutes affording the final product.

[0144] Sequential curing of QC4. A formulation of QC4 (100 mg), AuBPsso (5 OD) and HG-II (5 mol%) was prepared as described before. To initiate ADMET more efficiently the reaction was heated on a hotplate to 40 °C for one hour. After ADMET was complete the formulation was heated with PTH to 80 °C for 30 minutes affording a tough insoluble material.

[0145] Light patterning polymerization. The desired formulation (200 pl) was spread on a microscope slide placed on top of the masked LED. The spread formulation was irradiated for 15 minutes at 100 °C. Temperature was regulated with a thermal camera (FLIR One Edge).

[0146] Ultra-violet visible (UV-Vis) light spectrophotometer. A Thermo Scientific Evolution 220 UV-Vis spectrophotometer was used to determine AuBP solution’s localized surface plasmon resonance (LSPR) activation wavelength and optical density (OD). Samples were diluted to less than 1 OD to obtain accurate measurements.

[0147] Transmission electron microscope (TEM). TEM images were obtained using a Thermo Fisher Scientific (FEI) Talos F200C transmission electron microscope operating at 200 kV. The images were taken with Ceta 16M CMOS camera. Electron Microscopy Sciences formvar / carbon 200 Mesh, copper grids were prepared by adding 5 pl of an AuBP in ethanol solution (5 OD) to the grid surface and allowing it to evaporate under air.

[0148] Size exclusion chromatography (SEC). Molecular weights and polydispersity indices (PDIs) of the polymers were determined by size exclusion chromatography analyses in tetrahydrofuran (THF) at 35 °C using an Agilent 1260 Infinity II Quaternary system HPLCequipped with two Shodex SEC LF-804 Columns and one Shodex SEC KF-803. The flow rate was set to 1 mL / min. Detection was obtained with Agilent 1260 Infinity II Variable Wavelength Detector G7114A, Wyatt ViscoStar WV4-01 viscometer, Wyatt OPTILAB WOP1-01 refractometer, and Wyatt MALS DAWN WD3-02 laser light-scattering system. Prior to measurements, polymer solutions were filtered through Millipore 0.22 pm filters. Wyatt’s Astra 8.0.0.25 64-bit software was used for SEC data analysis and polymer properties calculation.

[0149] Nuclear magnetic resonance spectroscopy (NMR). NMR spectra were obtained with Bruker DPX 400 instrument; chemical shifts, given in ppm, are relative to the residual solvent peak of CDCI3 (7.26 ppm for!H NMR and 77.16 ppm for13C NMR). Polymer yields were calculated by integration of peaks taking the sum of NBD, QC and polymer to be 100 % of the sample and keeping a fixed range between samples with the same product.

[0150] Luzchem LZC-ORG photoreactor. Preparative synthesis of QCs was carried out using a Luzchem LZC-ORG photoreactor equipped with 313nm lamps. Samples were irradiated in quartz cuvettes in batches of several ml depending on availability of NBD.

[0151] High-resolution mass spectrometry (HRMS). A Q Exactive™ Focus mass spectrometer by Thermo Fisher equipped with an ESI probe was utilized for mass spectrometry analyses.EXAMPLE 1NBD - QC Isomerization and photothermal Retro-Cycloaddition

[0152] First, two diester monomers (Fig. 2, NBDI,2 and accordingly QCI,2) were synthesized. Using NBD solutions in dichloromethane (DCM), the intramolecular [2+2] photocycloaddition reaction to QC by irradiation with 313 nm light (Fig. 2a-c, Methods) was probed. The carbonyl group-based R1 and R2 attached to the NBD framework enabled self-sensitization, providing a unimolecular process. The results demonstrated that both monomers achieved full conversion to QC within an hour (Fig. 2b), delivering efficient access to the latent isomers (Methods). NBD derivatives with carbonyl-based R1 and R2 resulted in more stable QC with lower tendency towards RCA.

[0153] Next, the thermally induced RCA was studied by comparing the reaction under conventional heating (CHeat) and photothermal heating (PTH) (Fig. 2d-I, Methods). PTH significantly accelerated the reaction rate for both QCi and QC2. Thus, CHeat without solvent at 100 °C for 5 hours yielded less than 5% NBD, whereas the PTH-induced reaction, under otherwiseidentical conditions, produced 45% and 72% of NBDi and NBD2, respectively (Fig. 2e). As a control experiment, a catalytic effect from the silica surface encapsulating the nanoparticles was ruled out by including AuBPs in reactions heated by a hotplate (CHeat). To further explore this, several experiments with QCi at varying temperatures and AuBP concentrations (Fig. 2g-i) were carried out. Increasing the temperature further highlighted the differences between the heating methods, with PTH achieving quantitative conversions at 120 °C, while CHeat only reaching full conversion at 160 °C (Fig. 2g). Interestingly, higher AuBP concentrations resulted in increased conversions, even though the bulk temperature differences between the reactions were only observed for the first minute of the 5-hour reaction (Fig. 2h,i). Thus, the ease of access to QCs from NBDs and the high efficiency of the PTH-induced reaction suggest that the tested QC derivatives could serve as a promising platform to explore the concept of monomer-based switchable polymerizations.

[0154] Before attempting polymerization of the latent monomers, we sought to gain a deeper understanding of the photothermal RCA process. To this end, a series of reactions comparing different heating methods were conducted to identify the key factors involved (Fig. 3a). In one reaction, the surface chemistry of AuBPs was modified with octyl silane to decrease surface polarity (CsAuBPsso). In another, the dimensions of AuBPs were adjusted to shift the optimal photothermal activation wavelength to 660 nm. Additionally, reactions were carried out in both toluene and dimethyl sulfoxide (DMSO) solutions (0.1 M QCi), to investigate whether solvent polarity may affect the reaction (Fig. 3a). Notably, photothermal enhancement of the reaction occurred only under neat conditions (in absence of solvent), regardless of the changes in other parameters such as surface chemistry and activation wavelength, which only showed minor effects. To further probe this discovery, a reaction was carried out in a concentrated solution of QCi with both solvents (2.5 M, corresponding to 50% v / v), providing a noticeable enhancement under the PTH method, but without changing the conversions for standard CHeat (Fig. 3b).EXAMPLE 2Latent monomer polymerization

[0155] Naturally, the next step was to attempt polymerization starting from the dormant monomers. Thus, the widely used second-generation Hoveyda-Grubbs M720 metathesis catalyst (HG-II, 1 mol%) was mixed with QCi or 2 and AuBPs50or660 (5 OD, Fig. 4a) and ROMP at varioustemperatures (60, 80, 100, 120 °C) was attempted using both heating methods. To our delight, NMR analyses confirmed that the expected polymer formation in all sixteen experiments occurred only upon heating. Size exclusion chromatography (SEC) further supported these findings and showed polymer properties to be similar between heating methods. Consistent with our previous observations, PTH led to significantly faster polymerization, likely due to accelerated NBD formation (Fig. 4b). Increasing the temperature further accelerated the reaction and, interestingly, triggered a crosslinking mechanism that afforded an insoluble polymeric material. At 60 °C, crosslinking was observed only after polymer formation ceased, possibly indicating that all active catalyst had decomposed. The maximum yield of soluble polymer was achieved at 80 °C, with approximately 55 to 70% monomer consumption, depending on the QC derivative and heating method. Regarding the crosslinking mechanism, it is possible that the acrylate moiety reacts by a radical reaction, leading to bond formation between chains.

[0156] To gain further insight into the polymerization process, NMR spectra from reactions carried out at 80 °C with QC2 were analyzed as the reaction progressed (Fig. 4c, d). The results indicate that polymerization slows down as more monomer is consumed and NBD2 accumulates during the initial stages, eventually leveling off at approximately 10% of the initial amount of latent monomer (Fig. 4c, d). Predictably, increasing catalyst loading accelerated polymerization; however, it also unexpectedly led to faster crosslinking (Fig. 4e). This suggests that catalyst decomposition byproducts might serve as radical initiators, causing increased crosslinking. Additionally, we examined whether higher concentrations of AuBPs would result in rapid monomer activation (Fig. 2h) and thus a more efficient polymerization reaction. However, experiments revealed no significant difference between the various nanoparticle concentrations tested.

[0157] After successfully initiating polymerization by both thermal and photothermal activation, a different initiator was used to broaden the scope of the process (Fig. 4f). Thus, the latent monomer was mixed with the thermally latent Bis-CAAC catalyst, which features an active cyclicalkylamino carbene (CAAC) and an indenylidene moiety (Fig. 4f). Notably, polymerizing QC2 with Bis- CAAC yielded results comparable to those with HG-II, while also delaying crosslinking. The monomer scope was also expanded by synthesizing a bulky tert-butyl QC derivative (QC3), completing a series of three diester monomers and demonstrating the potential to control the final polymer substituents and thereby possibly tune the material properties (Fig. 4g).

[0158] Unexpectedly, a significant increase in RCA was observed when conducted under ROMP conditions (i.e., in the presence of a Ru metathesis catalyst). In the polymerization reaction shown in Fig. 4d, nearly 70% of QC2 was converted to NBD2 within 5 hours at 80 °C (most of which eventually polymerized). In contrast, when RCA was conducted without the catalyst, only minimal conversion was detected within 5 hours at 100 °C (<5%, Fig. 3a first column from right). We hypothesized that the Ru catalyst might be assisting the RCA reaction. Moreover, the subsequent polymerization could be driving the QC / NBD equilibrium towards NBD by consuming the ROMP monomer. To isolate these effects and properly understand their role, we designed two systems that would prevent the polymerization reaction by modifying either the monomer or the catalyst (Fig. 5a). To prevent monomer polymerization in the presence of an active metathesis catalyst, four methyl groups were added to the QCi skeleton (QCtet) to provide a hindered tetra- substituted double bond upon NBD formation. In the second strategy, a latent diiodo-Ru metathesis catalyst was used, which is incapable of initiating ROMP. Additionally, the RCA of QCi was also investigated in the presence of ruthenium chloride to determine whether the structure and oxidation state of the metathesis catalysts influenced the reaction (Fig. 5a).

[0159] The results of these experiments were remarkable. Heating QCtet to 100 °C showed a significant increase in conversion to the corresponding NBD in the presence of HG-II (Fig. 5b). Moreover, both the diiodo Ru catalyst and RuCh exhibited similar positive effects on RCA compared to the control without any additive, although they were less effective than reactions that included exothermic ROMP (Fig. 5c). These experiments led us to conclude that ruthenium indeed bolsters the RCA reaction, while additional heat obtained from the polymerization readily accelerates the consumption of the latent QC monomers.EXAMPLE 3Formulation stability and applications

[0160] Exclusive initiation solely upon exposure to an external stimulus is crucial for achieving temporal control of a reaction and represents a major challenge in developing such systems. Thus, the stability of the latent monomer, nanoparticle, and initiator mixtures was studied. To this end, polymerization-ready formulations were prepared using both QCi and QC2 with HG-II (1 mol%) and AUBP85O (5 OD), and their composition was monitored over time by NMR. Remarkably, no significant changes were detected after two weeks of storage. The experiments were repeated withstorage at 4 °C to prevent temperature fluctuations and ensure reproducibility. Under these conditions, formulations were tested every three days and kept for seven weeks without any sign of QC degradation or formation of NBD, and only minor catalyst decomposition. Additionally, identical batches were prepared for both monomers and successfully polymerized photothermally after three weeks of storage, showing no significant change in reactivity. These results represent a major leap when comparing to traditional catalyst-centered latency systems, where background polymerization can render formulations unusable in a matter of hours. The exceptional stability of the formulation underscores the applicative potential of this methodology paving the way to innovative applications, such as in 3D printing.

[0161] To this end, two polymerization systems, that would otherwise be inaccessible, were designed based on a latent monomer approach. The first system was planned to produce a di-block copolymer in a one-pot reaction by combining an active monomer with a latent monomer (Fig. 6a). To achieve this, HG-II (1 mol % in respect to QC2) and AuBPsso (5 OD) were added to a solution of NBDi (2 equivalents) and QC2 (1 equivalent), immediately triggering the ROMP of NBDi (Fig. 6b). NMR analysis confirmed full conversion within 10 minutes, with QC2 remaining completely inert under these conditions. The resulting viscous mixture was then photothermally heated to 80 °C for 20 minutes, inducing RCA and initiating the ROMP of NBD2 (Fig 6b). Subsequent NMR confirmed polymerization of the latent monomer, and SEC analysis revealed a clear shift toward higher molecular weight species, consistent with successful chain extension without concurrent polymerization (Fig 6b, c). Thus, this strategy enabled the formation of a ROMP-derived di-block copolymer without requiring the addition of any external reagent to the mixture.

[0162] For the second system a Janus type monomer featuring a dormant double bond within the QC framework and free alkenes on the peripheral ester substituents was synthesized (QC4). We reasoned that this structural arrangement could facilitate a sequential curing process. Initially, a soluble polymer may be formed through acyclic diene metathesis (AD MET) polymerization of the exposed terminal alkenes, leaving the “prospective” strained double bond on the QC intact. Upon heating, RCA would reveal the NBD olefin, enabling fast crosslinking of the polymer chains (Fig. 6d). To test this, the ADMET of QC4 was carried out with HG-II (5 mol%) at 40 °C (CHeat) in the presence of AuBPsso (5 OD) (Fig. 6e). The one-hour reaction yielded a soluble polymer as expected. Next, the ADMET product was photothermally heated as before (30 min, 80 °C, 850 nm), resulting in an insoluble material, indicating successful crosslinking. The polymerizationsystems described above highlight the unique reactivity offered by the latent monomer and suggest the great potential of this concept to unlock new opportunities for innovative materials research.

[0163] Finally, the spatial control offered by the photothermal methodology was tested. Light patterns projected onto the latent formulations were controlled with custom masks prepared using a commercial 3D printer. The mask was placed between the LED and a microscope slide where formulations were spread, providing a straightforward experimental setup (Fig. 6f). Two different formulations with a circular pattern projected onto them were irradiated. The first included QCi, HG-II (1 mol%) and AuBPsso (5 OD), while the second formulation contained the intermediate product after ADMET polymerization of QC4, as described in figure 6d, before crosslinking. Both experiments demonstrated excellent spatial control as observed by digital and thermal images (Fig. 6e). These findings, together with the demonstrated stability of the formulation, represent a significant step towards 3D printing applications.

[0164] Although the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications, and variations will be apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications and variations that fall within the spirit and broad scope of the appended claims.

[0165] All publications, patents and patent applications mentioned in this specification are herein incorporated in their entirety by reference into the specification, to the same extent as if each individual publication, patent or patent application was specifically and individually indicated to be incorporated herein by reference. In addition, citation or identification of any reference in this application shall not be construed as an admission that such reference is available as prior art to the present invention. To the extent that section headings are used, they should not be construed as necessarily limiting.

Claims

CLAIMSWhat is claimed is:

1. A polymerizable composition comprising a latent ring-opening metathesis polymerization (ROMP) precursor and a ROMP catalyst, wherein said latent ROMP precursor is represented by Formula 1 :wherein each of R1 and R2 is independently selected from H, optionally substituted alkyl, optionally substituted alkenyl, -C(=O)OR, -C(=S)OR, -C(=NH)OR, - C(=O)NHR, -C(=S)NHR and -C(=NH)NHR, or wherein R1 and R2 are interconnected to form a 4-8 membered saturated or unsaturated ring; wherein R is selected from H, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted cycloalkyl, optionally substituted heterocyclyl, optionally substituted aryl, optionally substituted heteroaryl and optionally substituted alkyl-cyclyl; wherein said cyclyl is selected from cycloalkyl, heterocyclyl, aryl and heteroaryl.

2. The polymerizable composition of claim 1, wherein: i. R1 and R2 represent the same or different substituents, and wherein each of R1 and R2 is -C(=O)OR; ii. R is selected from optionally substituted alkyl, optionally substituted alkenyl, and optionally substituted alkyl-cyclyl, or both (i) and (ii).

3. The polymerizable composition of claim 1 or 2, wherein R is selected from optionally substituted C1-C10 alkyl, optionally substituted C2-C10 alkenyl, and optionally substituted (C1-C10) alkyl-(3-14-membered)-cyclyl; wherein said (3-14-membered)cyclyl is selected from (C3-C14)cycloalkyl, (3-14-membered)heterocyclyl, (C6-C14) aryl and (5-14- membered)heteroaryl.

4. The polymerizable composition of any one of claims 1 to 3, wherein said latent ROMP precursor is represented by Formula 2:wherein each XI is independently selected from O, S, NH and NR; wherein each X is independently a bond or is selected fromO, S and NH; and wherein R is an optionally substituted alkenyl.

5. The polymerizable composition of claim 4, wherein R is an optionally substituted C2-C10alkenyl.

6. The polymerizable composition of any one of claims 1 to 5, wherein said ROMP catalyst is a Ru-complex based Grubbs-type catalyst.

7. The polymerizable composition of claim 6, wherein said Ru-complex is selected from Ru-carbene and Ru-alkylidene complex.

8. The polymerizable composition of any one of claims 1 to 7, wherein said ROMP catalyst is present in the polymerizable composition at an amount between 0.1 and 50mol%, or between 0.5 and 10mol% relative to the latent ROMP precursor.

9. The polymerizable composition of any one of claims 1 to 8, wherein upon heating the polymerizable composition the latent ROMP precursor is configured to undergo isomerization to a norbornadiene isomer thereof; and wherein the norbornadiene isomer is configured to undergo polymerization in-situ.

10. The polymerizable composition of claim 9, wherein said heating comprises a temperature of between 50 and 300°C or between about 60 and about 150°C.

11. The polymerizable composition of any one of claims 1 to 10, further comprising a plasmonic material.

12. The polymerizable composition of claim 11, wherein said plasmonic material is characterized by a photothermal activation wavelength in a range between 400 and 1200 nm;and wherein said plasmonic material is in a form of a plurality of particles each particle is a plasmonic nanoparticle encapsulated by an oxide shell.

13. The polymerizable composition of claim 11 or 12, wherein said plurality of particles is characterized by an average particle size between 100 nm and 500um, determined based on TEM imaging; wherein the plasmonic nanoparticle is characterized by a particle size between 10 and 500 nm, determined based on TEM imaging.

14. The polymerizable composition of any one of claims 11 to 13, wherein said oxide shell is or comprises a metalloid oxide, a metal oxide, or both.

15. The polymerizable composition of claim 14, wherein said metalloid oxide is silica; and wherein the plasmonic nanoparticle is a gold bipyramid.

16. The polymerizable composition of any one of claims 11 to 15, wherein: (i) a weight ratio between said plasmonic material and said latent ROMP precursor is between 1:100 and 1:1.000.000; (ii) a w / w concentration of said plasmonic material within said polymerizable composition is at least about 0.001%, or both (i) and (ii).

17. The polymerizable composition of any one of claims 1 to 16, further comprising an organic solvent; optionally wherein said latent ROMP precursor is characterized by a solubility within said organic solvent of at least O.Olg / L; and wherein the polymerizable composition is a liquid.

18. An article comprising the polymerizable composition of any one of claims 11 to 17.

19. The article of claim 18, being a 3D printing composition.

20. A method of synthesizing a ROM polymer, comprising providing the polymerizable composition of any one of claims 1 to 17; and inducing isomerization of the latent ROMP precursor to a norbornadiene isomer thereof; wherein the norbornadiene isomer undergoes ROM polymerization, thereby obtaining the ROM polymer.

21. The method of claim 20, wherein said inducing isomerization comprises heating said polymerizable composition to a temperature between about 50 and about 300°C or between 50 and about 150°C for a time period of at least 1 min.

22. The method of claim 21 , wherein the polymerizable composition is the composition of any one of claims 11 to 17; and wherein said heating comprises light irradiation.

23. The method of claim 22, wherein said light irradiation is at a wavelength range between 400 to 1200 nm.

24. The method of any one of claims 20 to 23, wherein said method further comprises shaping the polymerizable composition, thereby obtaining a shaped article; and wherein said shaping is performed prior to said inducing isomerization.

25. The method of claim 24, wherein said shaping is performed by a method selected from casting, molding and 3D printing.

26. The method of any one of claims 20 to 25, wherein said ROM polymer is a block co-polymer comprising a first block comprising an olefin metathesis polymer and a second block comprising the ROM polymer derived from the latent ROMP precursor; and wherein the method further comprises forming the first block by contacting a precursor of the olefin metathesis polymer with an olefin metathesis catalyst.

27. The method of claim 26, wherein said olefin metathesis polymer is a ROM polymer, and wherein the precursor of the olefin metathesis polymer is a cycloalkene, optionally wherein the cycloalkene is a cyclooctene.

28. A compound represented by Formula 1:wherein each of R1 and R2 is independently selected from optionally substituted alkenyl, -C(=O)OR, -C(=S)OR, -C(=NH)OR, -C(=O)NHR, -C(=S)NHR and -C(=NH)NHR, or wherein R1 and R2 are interconnected to form a 4-8 membered unsaturated ring; and wherein R is optionally substituted alkenyl.

29. The compound of claim 28, represented by Formula 2:or by Formula 2A:wherein each XI is independently selected from O, S, NH and NR; wherein each X is independently a bond or is selected from O, S and NH; and wherein R is an optionally substituted alkenyl.

30. The compound of claim 28 or 29, wherein R is optionally substituted C2-C10 alkenyl.

31. The compound of claim 29 or 30, wherein the compound is represented by Formula 2; and wherein XI and X are O.

32. A composition comprising: (i) the compound of any one of claims 28 to 31, (ii) a ROMP catalyst and optionally (iii) a plasmonic material.

33. The composition of claim 32, wherein said plasmonic material is in a form of a plurality of nanoparticles, each nanoparticle is encapsulated by an oxide shell; wherein an amount of the ROMP catalyst within the composition is between 0.1 and 50mol% or between 0.5 and 10mol%; and wherein a w / w concentration of said plasmonic material within said composite is at least 0.0001%.

34. The composition of claim 32 or 33, wherein said plasmonic material is characterized by an average particle size between 100 nm and 500um, determined based on TEM image, and wherein each nanoparticle is a plasmonic nanoparticle.

35. The composition of any one of claims 32 to 34, wherein said plasmonic nanoparticle is characterized by a particle size between 10 and 500nm, and wherein said oxide shell comprises a metalloid oxide, a metal oxide, or both; optionally wherein said metalloid oxide is silica; optionally wherein said plasmonic nanoparticle is a noble metal nanoparticle.

36. The composition of any one of claims 32 to 35, wherein said compound is latent ROMP precursor and wherein the composition is a polymerizable composition.

37. The composition of claim 36 and the polymerizable composition of any one of claims 1 to 17, wherein upon storage for at least 1 month at a temperature below 10C, said composition or said polymerizable composition is characterized by not more than 5%w / w reduction of an initial content of said latent ROMP precursor.

38. The composition of claim 37 and the polymerizable composition of any one of claims 11 to 17, configured to emit thermal energy upon light irradiation at a photothermal activation wavelength; wherein upon a plurality of repetitive photothermal activation and relaxation cycles said composition or the polymerizable composition retains at least 90% of the initial thermal energy; and wherein said plurality of repetitive photothermal activation and relaxation cycles comprises at least 50 cycles.

39. A method of synthesizing a ROM polymer, comprising providing the composition of any one of claims 32 to 38; inducing ADMET polymerization of said compound by heating the composition to a temperature suitable for initiation of ADMET polymerization, thereby obtaining a polymer; and crosslinking said polymer by inducing isomerization of the latent ROMP precursor to a norbornadiene isomer thereof; wherein the norbornadiene isomer undergoes ROM polymerization, thereby obtaining the ROM polymer.

40. The method of claim 39, wherein said inducing isomerization comprises heating said polymer to a temperature between about 50 and about 300°C or between about 50 and about 150°C; and wherein said heating is by (i) thermal heating or (ii) light irradiation.

41. The method of claim 40, wherein said light irradiation is at a wavelength range between 400 to 1200 nm and for a time period of at least Imin.

42. The method of any one of claims 39 to 41, wherein said method further comprises shaping the polymerizable composition, thereby obtaining a shaped article; and wherein said shaping is performed prior to said crosslinking.

43. The method of any one of claims 39 to 42, wherein said polymer is represented by Formula 3:, wherein each of X and XI is independently selected fromO, S and NH, wherein n is an integer being between 1 and 8, and wherein m represents an integer being between 100 and 100000.

44. The method of any one of claims 39 to 43, wherein said ROM polymer is represented by Formula 4:wherein k represents an integer being between 100 and100000.

45. A latent ring-opening metathesis polymerization (ROMP) precursor represented byFormula 1:, wherein each of R1 and R2 is independently selected from H, optionally substituted alkyl, optionally substituted alkenyl, -C(=O)OR, -C(=S)OR, -C(=NH)OR, - C(=O)NHR, -C(=S)NHR and -C(=NH)NHR, or wherein R1 and R2 are interconnected to form a 4-8 membered saturated or unsaturated ring; wherein R is selected from H, optionally substituted alkyl, optionally substituted alkenyl, optionally substituted cycloalkyl, optionally substituted heterocyclyl, optionally substituted aryl, optionally substituted heteroaryl and optionally substituted alkyl-cyclyl; wherein said cyclyl is selected from cycloalkyl, heterocyclyl, aryl and heteroaryl.

46. The latent ROMP precursor of claim 45, wherein R1 and R2 represent the same or different substituents, and wherein each of R1 and R2 is -C(=O)OR.

47. The latent ROMP precursor of claim 45 or 46, wherein R is selected from optionally substituted alkyl, and optionally substituted alkyl-cyclyl.

48. The latent ROMP precursor of any one of claims 45 to 47, wherein R is selected from optionally substituted C1-C10 alkyl, and optionally substituted (C1-C10) alkyl-(3-14- membered) -cyclyl; wherein said (3-14-membered)cyclyl is selected from (C3-C14)cycloalkyl, (3-14-membered)heterocyclyl, (C6-C14) aryl and (5-14-membered)heteroaryl.

49. The latent ROMP precursor of any one of claims 45 to 48, wherein upon heating the latent ROMP precursor is configured to undergo isomerization to a norbornadiene isomer thereof.

50. The latent ROMP precursor of claim 45 or 46, wherein said latent ROMP precursor is represented by Formula 2:wherein each XI is independently selected from O, S, NH and NR; wherein each X is independently a bond or is selected fromO, S and NH; and wherein each R independently is an optionally substituted alkenyl.

51. The latent ROMP precursor of claim 50, wherein R is an optionally substituted C2- ClOalkenyl.

52. The latent ROMP precursor of claim 50 or 51, configured to undergo ADMET polymerization via said R and further configured to undergo isomerization to a norbornadiene isomer thereof.

53. The latent ROMP precursor of claim 49 or 52, wherein the norbornadiene isomer is configured to undergo ROM polymerization under presence of a ROMP catalyst.

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