A method and apparatus for forming vascular-like channels involves liquid-in-liquid 3D printing utilizing two polymer solutions used as a printing ink and a matrix. Anionic polyacrylamide (APAM) is one of the polymer solutions and acts as the matrix material. Chitosan is the other polymer solution and acts as the printing ink. The chitosan printing ink is extruded through a print nozzle of a 3D printer onto the APAM matrix which covers the bottom of a petri dish while the nozzle is moved in a desired pattern for the channels. The chitosan and APAM polymer complexes self-assemble on the ink-matrix interface, locking chitosan polymers inside the matrix before they can spread and causing the formation of soft elastic membranous walls. The chitosan ink and APAM matrix can be removed after the polymer complex self-assembly. The printed chamber with membranous walls allows for liquid infusion to work as fluidic channels.

The present invention provides a resin composition for stereolithography that is easily shapable with good shape precision while reducing sedimentation of inorganic particles during storage, and a obtained three-dimensional shaped article thereby excels in mechanical characteristics such as flexural strength and flexural modulus, in addition to having a desirable shade and good shade stability. The present invention relates to a resin composition for stereolithography comprising a polymerizable monomer (a), a photopolymerization initiator (b), an inorganic particle (c) having an average particle diameter of 5 to 500 nm, and a hindered phenolic compound (d), wherein the content of the photopolymerization initiator (b) is 0.1 to 10 parts by mass relative to 100 parts by mass of the polymerizable monomer (a), the content of the inorganic particle (c) is 50 to 400 parts by mass relative to 100 parts by mass of the polymerizable monomer (a), and the content of the hindered phenolic compound (d) is 0.1 to 500 parts by mass relative to 100 parts by mass of the photopolymerization initiator (b).

A photo-curable resin composition for three-dimensional shaping includes a polyfunctional radical polymerizable compound (A), a monofunctional radical polymerizable compound (B), polyethylene particles (C), and a curing agent (D). The polyfunctional radical polymerizable compound (A) is a single polyfunctional radical polymerizable compound having an ethylenically unsaturated group equivalent of 700 g/eq or more and 8,000 g/eq or less or a mixture including a plurality of types of polyfunctional radical polymerizable compounds and having an ethylenically unsaturated group equivalent of 700 g/eq or more and 8,000 g/eq or less, the ethylenically unsaturated group equivalent being a weighted average of ethylenically unsaturated group equivalents of the polyfunctional radical polymerizable compounds in terms of weight ratio. A content of the polyethylene particles (C) is 5 parts by mass or more and 50 parts by mass or less relative to 100 parts by mass of a total of the polyfunctional radical polymerizable compound (A) and the monofunctional radical polymerizable compound (B).

Provided are devices and methods that combine material anisotropy with nonlinear structural design to produce structures that precisely and sequentially actuate in response to multiple stimuli, such as water or non-polar solvents. These devices and methods can include bistable anisotropic elements that convert to monostable element upon exposure to a particular stimulus, and anisotropic distortions can be harnessed to change the geometric properties of the element to cross phase boundaries and trigger shape changes at precise times. One can incorporate complex logic into these devices and methods.

The present invention includes methods for forming an object in a volume including a photohardenable composition described herein that includes a photohardenable resin component and a photoswitchable photoinitiator comprising a P-type photochromic molecule. The present invention also includes photoswitchable photoinitiators comprising a P-type photochromic molecule, preferably comprising a P-type diarylethene molecule, and photohardenable compositions and methods including such photoswitchable photoinitiators.

Photoswitchable photoinitiators comprising a naphthopyran molecule including one or more substituents wherein at least one substituent comprises a substituted or unsubstituted diaryl ketone moiety are disclosed. Photohardenable compositions and methods for forming an object in a volume and products thereof, which photohardenable compositions and methods include such photoswitchable photoinitiator, are also disclosed.

A method of making a polyimide (PI)-based material. In one embodiment, the method begins by dispersing a polyamic acid (PAA) oligomer and photo-initiator into a photo-reactive monomer to form a liquid resin. In contrast to the above-described prior art, the liquid resin is substantially devoid of any non-reactive solvents. Electromagnetic radiation is then applied (e.g., in a 3D printing operation) to solidify the liquid resin and to substantially form a interpenetrating polymer network (IPN) in which the PAA oligomer is entangled within the network formed by the photo-reactive monomer but remains substantially independent and un-crosslinked from the PAA oligomer. Thereafter, the PAA-based IPN is thermally cycled to form a polyimide-based IPN.

A method of printing a hydrogel-based device includes contacting a monomer, a crosslinker, a photoinitiator, and a precursor salt with a solvent to form an ink solution, printing the ink solution onto a substrate, exposing the ink solution to light, sufficient to form a hydrogel, and contacting the hydrogel with a reducing agent sufficient to precipitate nanoparticles from the precursor salt in the hydrogel.