A lacquer composition is provided, comprising 20%-79.9% by weight, based on the total weight of the composition, of a thiol compound having two or more thiol groups, 20%-79.9% by weight, based on the total weight of the composition, of a compound having two or more carbon-carbon double bonds and 0.1%-10% by weight, based on the total weight of the composition, of a separating agent having an alkyl radical having 4-20 carbon atoms, where the alkyl radical is unsubstituted or fluorine-substituted and the alkyl radical is bonded to a functional group. Also provided are the use of this lacquer composition as a protective lacquer on an optical surface of an optical element in the production of the optical element, and an optical element comprising the protective lacquer.

The present disclosure belongs to the technical field of polymer materials, and in particular relates to a chain extender and a preparation method and application thereof, a recyclable thermosetting polyurethane and a preparation method thereof. The present disclosure provides a chain extender whose chemical formula is shown in formula I. The chain extender provided by the present disclosure contains two types of dynamic covalent bonds, and the total number of dynamic covalent bonds is 4. The thermosetting polyurethane prepared by the provided chain extender has better hot-pressing repair efficiency. The results of the examples show that under the same hot-pressing conditions, the repair efficiency of the thermosetting polyurethane prepared by the 4,4′-dithiodianiline chain extender is 59%. The repair efficiency of thermosetting polyurethane is 97%, which is significantly improved.

A method of making an ink for use in additive manufacturing of a self-healable and shape-memorizable product includes mixing a diol with isophorone diisocyanate, dimethylacetamide, and dibutyltin dilaurate to form a first solution. The method further includes mixing the first solution with 2-Hydroxyethyl disulfide to form a second solution. The method further includes mixing the second solution with 2-Hydroxyethyl methacrylate to form a third solution. The method further includes mixing the third solution with a tributylphosphine, a photoinitiator, and a photoabsorber to facilitate additive manufacturing of the ink.

Disclosed herein are self-healing oligomers according to the structure [UPy-(D.sub.m-U-D.sub.m)(.sub.2+q)]-[A(G)(.sub.n−1)-D.sub.m].sub.k-Z; wherein UPy, D, m, U, q, A, G, n, k, and Z are defined and described further herein, and wherein the oligomer possesses at least 3 urethane linking groups and comprises a backbone derived from a polyether polyol, a polyester polyol, a poly(dimethylsiloxane), a disulfide polyol, or combinations thereof. Also described and claimed are various compositions containing such oligomers as part of a self-healing component, wherein such compositions also include an optional reactive monomer and/or oligomer component and a photoinitiator component. Yet further described and claimed are articles cured from the compositions elsewhere described using the oligomers elsewhere described.

The present invention relates to a composition comprising 10 to 50 wt.-% of at least one polyisocyanate a-1) based on hexamethylene diisocyanate, comprising at least one oligomeric polyisocyanate based on hexamethylene diisocyanate and optionally monomeric hexamethylene diisocyanate and 50 to 90 wt.-% of at least one polyisocyanate a-2) based on isophorone diisocyanate, comprising at least one oligomeric polyisocyanate based on isophorone diisocyanate and optionally monomeric isophorone diisocyanate, with the proviso that at least one of the components a-1) and a-2) additionally comprises monomeric isocyanate of the named kind, as well as at least one sulfur-containing component. It has been shown that the above mentioned mixture of the specific isocyanate group containing components improves the thermal and mechanical properties of a cured composition. Thus prepared molded articles are particularly suitable for the preparation of spectacle lenses, inter alia due to these properties.

A method for preparing a transparent flexible polyurethane film includes the following steps: (1) mixing a hydroxyl-terminated polyalkylene carbonate diol, a diisocyanate compound, 2,2′-dithiodiethanol, dibutyltin dilaurate and a chloroalkane solvent, and then reacting at 40 to 60° C. for 0.5 to 3 h to obtain an isocyanate-terminated oligomer solution; and (2) adding a polyol cross-linking agent, a bistrifluoromethanesulfonimide lithium salt and a 1-ethyl-3-methylimidazole bistrifluoromethanesulfonimide salt to the isocyanate-terminated oligomer solution, reacting at 40 to 60° C. for 0.5 to 1.5 h, removing the chloroalkane solvent to obtain the transparent flexible polyurethane film.

The present disclosure belongs to the technical field of polymer materials, and in particular relates to a chain extender and a preparation method and application thereof, a recyclable thermosetting polyurethane and a preparation method thereof. The present disclosure provides a chain extender whose chemical formula is shown in formula I. The chain extender provided by the present disclosure contains two types of dynamic covalent bonds, and the total number of dynamic covalent bonds is 4. The thermosetting polyurethane prepared by the provided chain extender has better hot-pressing repair efficiency. The results of the examples show that under the same hot-pressing conditions, the repair efficiency of the thermosetting polyurethane prepared by the 4,4′-dithiodianiline chain extender is 59%. The repair efficiency of thermosetting polyurethane is 97%, which is significantly improved.

A crosslinked polymeric composition comprising A, B, C, D, and E units having the following structures, respectively:

##STR00001##

##STR00002##

##STR00003##

##STR00004##

##STR00005##

wherein dashed bonds represent optional bonds; the asterisks (*) in C units represent covalent bond connection points with asterisks in A units and E units; the asterisks (*) in D units represent covalent bond connection points with asterisks in B units and E units; wherein a portion of E units are bound to C units, a portion of E units are bound to D units, and a portion of E units are bound to both C and D units; and the composition contains a multiplicity of A, B, C, D, and E units. Also described is a method for producing the crosslinked polymeric composition by reacting epoxy-containing molecules (A molecules), isocyanate-containing molecules (B molecules), and disulfide-containing molecules (C molecules).

Disclosed herein are methods for synthesizing oligomer mixtures with one or more moieties capable of forming a multi-hydrogen bonding dimer. The method comprises the steps of providing certain intermediate reaction products; adding a polyol component to the intermediate reaction product to yield an oligomer mixture comprising one or more multi-hydrogen bonding groups; and further reacting the mixture with certain isocyanate-reactive compounds to yield a multi-hydrogen bonding oligomer, wherein solvents comprise less than 50% of the total by weight of all reagents used in the synthesis of the multi-hydrogen bonding oligomer. Preferably, such methods involve no separation, distillation, or isolation of any intermediate product, and as such, they are particularly useful for a continuous or one-pot synthesis.

A self-restoring polyurethane-based polymer obtained by polymerization of a composition containing an aromatic disulfide diol represented by Chemical Formula, HO—Ar.sub.1—S—S—Ar.sub.2—OH, an alicyclic polyisocyanate, and a polyol. Ar.sub.1 and Ar.sub.2 each are independently a substituted or unsubstituted C.sub.6-C.sub.30 arylene group. The composition satisfies Equation, 0.1≤M.sub.[disulfide]/M.sub.[OH]. M.sub.[disulfide] is a total mole number of the aromatic disulfide diol in the composition, and M.sub.[OH] is a total mole number of the aromatic disulfide diol and the polyol in the composition.