公开(公告)号：US11618832B2

公开(公告)日：2023-04-04

申请号：US16325991

申请日：2017-08-17

Applicant: VIRGINIA TECH INTELLECTUAL PROPERTIES, INC.

Inventor： Maruti Hegde ,  Timothy E. Long ,  Viswanath Meenakshisundaram ,  Christopher B. Williams ,  Nicholas Chartrain

IPC: C08F2/46 ,  C08F2/50 ,  C08G61/04 ,  C09D11/101 ,  B33Y70/00 ,  C09D11/102 ,  B33Y10/00 ,  B29C64/135

Abstract: Polymer resins for the vat photopolymerization of thermoplastics are provided, in particular for the vat photopolymerization of thermoplastics with exception thermal stability and mechanical properties. In some aspects, the polymer resins are prepared by ring opening of an aromatic dianhydride with an alcohol containing an acrylate or methacrylate to produce a photocrosslinkable diacid monomer; conversion of the photocrosslinkable diacid monomer to a photocrosslinkable diacyl chloride; and polymerization of the photocrosslinkable diacyl chloride with an aromatic diamine to produce a photocrosslinkable precursor polymer. Upon crosslinking and drying, a thermal imidization can yield aromatic polyimide polymers with high yield and with micron-scale structural resolution.

公开(公告)号：US12285910B2

公开(公告)日：2025-04-29

申请号：US16954124

申请日：2018-12-15

Applicant: Virginia Tech Intellectual Properties, Inc.

Inventor： Nicholas Chartrain ,  Viswanath Meenakshisundaram ,  Christopher B. Williams

IPC: B29C64/255 ,  B29C64/124 ,  B29C64/135 ,  B29C64/209 ,  B29C64/245 ,  B29C64/264 ,  B29C64/295 ,  B33Y10/00 ,  B33Y30/00 ,  B33Y70/00 ,  C08F120/68 ,  C08F283/00 ,  C08F283/06 ,  C08L5/00 ,  B29K33/00 ,  B29K75/00 ,  B29K105/00 ,  B29L31/52

Abstract: In various aspects, top-down stereolithography apparatus and methods of use thereof are provided herein that allow for additive manufacturing of an article from a high-viscosity resin. The apparatus and methods can print resins having viscosities higher than conventional systems, e.g. viscosities up to about 100 Pa·s at the elevated temperature. The resin may have a room temperature viscosity of about 100 Pa·s, about 250 Pa·s, about 1000 Pa·s, or more. In some aspects, the resin is a solid at room temperature. The apparatus and methods do not rely upon solvents or other viscosity modifiers being added to the resin, and are capable of top-down additive manufacturing approaches which provide reduced stress on the printed article.