Directional Adhesion of Monodomain Liquid Crystalline Elastomers

Pressure-sensitive adhesives (PSAs) are widely employed in consumer goods, health care, and commercial industry. Anisotropic adhesion of PSAs is often desirable to enable high force capacity coupled with facile release and has typically been realized through the introduction of complex surface and/or bulk microstructures while also maintaining high surface conformability. Although effective, microstructure fabrication can add cost and complexity to adhesive fabrication. Here, we explore aligned liquid crystalline elastomers (LCEs) as directional adhesives. Aligned LCEs exhibit direction-dependent stiffness, dissipation, and nonlinear deformation under load. By varying the cross-link content, we study how the bulk mechanical properties of LCEs correlate to their peel strength and peel anisotropy. We demonstrate up to a 9-fold difference in peel force measured when the LCE is peeled parallel vs perpendicular to the alignment axis. Opportunities to spatially localize adhesion are presented in a monolithic LCE patterned with different director orientations

APPLICATIONS OF OXYGEN FOR NO x CONTROL AND CO 2 CAPTURE IN COAL-FIRED POWER PLANTS by

ing com bus tion mod i fi ca tion ap proaches ap pli ca ble to pul ver-ized coal fired boil ers are pre sented: “Ox y gen-En riched Com bus tion” (OEC) for NOx con trol and “Oxy-Com bus tion ” (PC-OC) for CO2 cap ture. Ox y gen-en riched air rather than air is used as an ox i dizer in the OEC tech-nol ogy. Un like flue gas treat ment tech nol o gies, OEC di rectly im pacts the NOx for ma tion pro cess by sig nif i cantly re duc ing the con ver sion of coal bound ni tro gen to NOx. Pi lot-scale and full-scale tests have shown 20 to 30 % NOx re duc tion from an op ti mized staged-air base line. In ad di tion to the over all cost com pet i tive ness and the re duced cap i tal re quire ments, other sig nif i cant ad van tages of the O2-en riched tech nol ogy vs. ex ist ing low NOx tech nol o gies are pre sented. The PC-OC tech nol ogy is shown as a cost-ef fec tive tech nol ogy for CO2 cap-ture from ex ist ing or new coal-fired power plants. Pure ox y gen di luted in re cy cled flue gases is used as an ox i dizer. The pro cess has been suc cess fully dem on strated and ex ten sively char ac ter ized at pi lot-scale level (1.5 MWt). The tests have shown sub stan tial ben e fits of the PC-OC tech nol ogy, in terms of NOx re duc tion (60-70 % from air-base line), over all plant ef fi ciency, etc. The cost ef fec tive ness of this cap ture tech nol ogy com pared to com pet i tive amine scrub bing tech nol ogy was in ves ti gated. The cost of CO2 avoided was around $36/ton for the new PC-OC cases, about$48/ton on a ret ro fit PC-OC case, which is about 25 to 40 % cheaper than the amine scrub bing sys tem. Those num bers were cal cu lated for sub-crit i cal units and in clude the cost of CO2 com pres sion up to 80 bar

Directional Adhesion of Monodomain Liquid Crystalline Elastomers

Pressure-sensitive adhesives (PSAs) are widely employed in consumer goods, health care, and commercial industry. Anisotropic adhesion of PSAs is often desirable to enable high force capacity coupled with facile release and has typically been realized through the introduction of complex surface and/or bulk microstructures while also maintaining high surface conformability. Although effective, microstructure fabrication can add cost and complexity to adhesive fabrication. Here, we explore aligned liquid crystalline elastomers (LCEs) as directional adhesives. Aligned LCEs exhibit direction-dependent stiffness, dissipation, and nonlinear deformation under load. By varying the cross-link content, we study how the bulk mechanical properties of LCEs correlate to their peel strength and peel anisotropy. We demonstrate up to a 9-fold difference in peel force measured when the LCE is peeled parallel vs perpendicular to the alignment axis. Opportunities to spatially localize adhesion are presented in a monolithic LCE patterned with different director orientations

Directional Adhesion of Monodomain Liquid Crystalline Elastomers

Pressure-sensitive adhesives (PSAs) are widely employed in consumer goods, health care, and commercial industry. Anisotropic adhesion of PSAs is often desirable to enable high force capacity coupled with facile release and has typically been realized through the introduction of complex surface and/or bulk microstructures while also maintaining high surface conformability. Although effective, microstructure fabrication can add cost and complexity to adhesive fabrication. Here, we explore aligned liquid crystalline elastomers (LCEs) as directional adhesives. Aligned LCEs exhibit direction-dependent stiffness, dissipation, and nonlinear deformation under load. By varying the cross-link content, we study how the bulk mechanical properties of LCEs correlate to their peel strength and peel anisotropy. We demonstrate up to a 9-fold difference in peel force measured when the LCE is peeled parallel vs perpendicular to the alignment axis. Opportunities to spatially localize adhesion are presented in a monolithic LCE patterned with different director orientations