PUMA publications for /tag/HumidityTue Mar 25 13:26:59 CET 2025Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciencesmar2309Complex Poisson’s ratio for viscoelastic materials: direct and indirect measurement methods and their correlation4812025humidity mechanical mib mib_ls2 myown Mon May 16 22:43:23 CEST 2022Journal of Materials Science209508-9524Influence of humidity on the rheology of thermoresponsive shape memory polymers572022analysis experiment humidity mechanical mib mib_ls2 myown shape-memory Shape Memory Polymers (SMPs) have the inherent ability to maintain a reversible temporary shape and restore a permanent shape under an external trigger. The class of materials has great potential to contribute to smart applications in soft robotics, aerospace, actuation and biomedicine. In these potential application domains, materials are often exposed to large fluctuations due to humidity influences. Therefore, a novel approach is developed to characterize the strongly coupled thermal, humidity and time-dependent behavior of polyurethane-based SMP. Weight gain measurements with disk samples of dimension 35$$\,\times $$35 $$\times $$1.5 $$\text {mm}^\text {3}$$and linear expansion tests with rectangular samples of dimension 10 $$\times $$40 $$\times $$1.0 $$\text {mm}^\text {3}$$at different relative humidity are carried out to perform the isothermal and isohumid dynamic measurements in thermodynamic equilibrium. The time-temperature superposition is used to characterize and compare the viscoelastic properties at different relative humidity. Concerning effective material properties, a major finding of this investigation is the horizontal shift of the material parameter in the temperature space due to the presence of humidity. Thus, the humidity-dependent material behavior is fully described by a humidity-dependent glass transition temperature. The measured experiments provide a full description of the thermal, humidity and mechanical behavior of SMPs.Thu Jan 20 13:52:02 CET 20221-6The facade and roofing system that is ventilating in dry conditions and enclosing in humid weather2019building climate envelope facade humidity myown pine relative responsive temperature wood Wed Oct 13 14:12:55 CEST 2021{Humidity and thermal triggered Shape Memory Effect - Rheology-based numerical modelling - Dynamic Mechanical Thermal Humidity Analysis}2021Analysis Dynamic Humidity Mechanical Thermal mydata myown Wed Oct 13 14:11:25 CEST 2021Advanced Materials92007982From Understanding Mechanical Behavior to Curvature Prediction of Humidity-Triggered Bilayer Actuators332021PEDOT:PSS actuators bilayer curvature humidity mechanical myown prediction properties trigger Abstract Nature will always be an endless source of bioinspiration for man-made smart materials and multifunctional devices. Impressively, even cutoff leaves from resurrection plants can autonomously and reproducibly change their shape upon humidity changes, which goes along with total recovery of their mechanical properties after being completely dried. In this work, simple bilayers are presented as autonomously moving, humidity-triggered bending actuators. The bilayers—showing reproducible bending behavior with reversible kinematics and multiway behavior—are studied in terms of their mechanical behavior upon humidity changes. The active layer consists of a highly conducting polymer film based on poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) with poly(dimethylsiloxane) (PDMS) as passive layer. The response to humidity is explored with dynamic mechanical thermal analysis and quartz crystal microbalance measurements. Introduction of a composite beam model allows to predict the curvature of the actuators with input from the rheological measurements. It is clearly demonstrated that volumetric strain and Young's modulus, both heavily influenced by the water uptake, dominate the bending behavior and therefore the curvature of the actuators. This loop of rheological characterization coupled with an analytical model allows to predict curvatures of in principle any complex geometry and material combination for moving parts in soft robotics.Tue Jul 21 14:18:18 CEST 2020Advanced Online Moisture Measurements in Power Transformers2006Aging Humidity Moisture Monitoring Oil Power Transformer insulation measurement paper Tue Jul 14 15:23:14 CEST 2020The Breakdown Voltage of Insulation Oil under the Influence of Humidity, Acidity,Particles and Pressure 2007Acidity Breakdown Humidity Insulation Oil Particles Pressure Voltage Fri Jan 17 11:15:04 CET 2020Art in transit: Studies in the transport of paintings223--248Paintings: Their response to temperature, relative humidity, shock, and vibration1991humidity paintings vibration HumidityCommunity for tag(s) Humidity