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The proposed bi-functional protective structure intended to have hydrophilic interior towards the skin surface and hydrophobic exterior for protection, ensuring fast transfer of moisture between body and external environment. The sandwich structure is prepared using 100% wool jersey and varieties of 100% polyester fabrics. Hydrophilic treatments were given using cutinase (fusarium solani pisi) enzyme and commercial hydrophilic softener Ruco Pur Sly®. The polyester fabrics were given a hydrophobic treatment with Ruco Dry Eco® - a commercial cationic water repellent preparation. Variables include enzyme treatment time, and change in pressure to achieve suitable wet pick up at foulard. Several wool-polyester sandwich structures with optimum hydrophilic/hydrophobic properties were made by thermal adhesion using thin polyamide layer. Drop test and vapour permeability test were conducted to evaluate wetting properties and breathability of the samples. Sandwich structure comprising hydrophilic wool-jersey and hydrophobic PES spacer fabric showed the highest value for water vapour permeability. Paper written by the Saxion chair Smart Functional Materials and the Technical University of Iasi, Romania, for and accepted by the Autex Conference 2013.
MULTIFILE
Inkjet printing is a rapidly growing technology for depositing functional materials in the production of organic electronics. Challenges lie among others in the printing of high resolution patterns with high aspect ratio of functional materials to obtain the needed functionality like e.g. conductivity. μPlasma printing is a technology which combines atmospheric plasma treatment with the versatility of digital on demand printing technology to selectively change the wetting behaviour of materials. In earlier research it was shown that with μPlasma printing it is possible to selectively improve the wetting behaviour of functional inks on polymer substrates using atmospheric air plasma. In this investigation we show it is possible to selectively change the substrate wetting behaviour using combinations of different plasmas and patterned printing. For air and nitrogen plasmas, increased wetting of printed materials could be achieved on both polycarbonate and glass substrates. A minimal track width of 320 μm for a 200 μm wide plasma needle was achieved. A combination of N2 with HMDSO plasma increases the contact angle for water up from <100 to 1050 and from 320 to 460 for DEGDMA making the substrate more hydrophobic. Furthermore using N2-plasma in combination with a N2/HMDSO plasma, hydrophobic tracks could be printed with similar minimal track width. Combining both N2 -plasma and N2/HMDSO plasma treatments show promising results to further decrease the track width to even smaller values.
In this article we investigate the change in wetting behavior of inkjet printed materials on either hydrophilic or hydrophobic plasma treated patterns, to determine the minimum obtainable track width using selective patterned μPlasma printing. For Hexamethyl-Disiloxane (HMDSO)/N2 plasma, a decrease in surface energy of approx. 44 mN/m was measured. This resulted in a change in contact angle for water from <10 up to 105 degrees, and from 32 up to 46 degrees for Diethyleneglycol-Dimethaclylate (DEGDMA). For both the nitrogen, air and HMDSO/N2 plasma single pixel wide track widths of approx. 320 μm were measured at a plasma print height of 50 μm. Combining hydrophilic pretreatment of the glass substrate, by UV/Ozone or air μPlasma printing, with hydrophobic HMDSO/N2 plasma, the smallest hydrophilic area found was in the order of 300 μm as well.
Recent research by the renowned Royal Institution of Chartered Surveyors (RICS) shows that more than 2/3 of all CO2 is emitted during the building process and less than 1/3 during use to heat the building and the tap water. Lightweight, local and biobased materials such as biocomposites to replace concrete and fossil based cladding are in the framework of climate change, a necessity for future building. Using plant fiber in polymer composites is especially interesting for construction since natural fibers exhibit comparative good mechanical properties with small specific weight, which defines the potential for lightweight constructions. The use of renewable resources, will affect the ecosystem favorably and the production costs of construction materials could also decrease. However, one disadvantage of natural fibers in plastics is their hydrophilic properties. In construction the materials need to meet special requirements like the resistance against fluctuating weather conditions (Ticoalu et al., 2010). In contrast to synthetic fibers, the natural ones are more moisture- and UV-radiation-sensitive. That may lead to degradation of these materials and a decreasing in quality of products. (Lopez et al., 2006; Mokhothu und John, 2017) Tanatex and NPSP have approached CoE BBE/Avans to assist in a study where fibres impregnated with the (modified) Tanatex products will be used for reinforcement of thermoset biopolymers. The influence of the different Tanatex products on the moisture absorption of natural/cellulosic fibers and the adhesion on the fibers on main composite matrix will be measured. The effect of Tantex products can optimize the bonding reaction between the resin and the fibers in the (bio) composite and result to improved strength and physico-chemical properties of the biocomposite materials. (word count: 270)
Buildings are responsible for approximately 40% of energy consumption and 36% of carbon dioxide (CO2) emissions in the EU, and the largest energy consumer in Europe (https://ec.europa.eu/energy). Recent research shows that more than 2/3 of all CO2 is emitted during the building process whereas less than 1/3 is emitted during use. Cement is the source of about 8% of the world's CO2 emissions and innovation to create a distributive change in building practices is urgently needed, according to Chatham House report (Lehne et al 2018). Therefore new sustainable materials must be developed to replace concrete and fossil based building materials. Lightweight biobased biocomposites are good candidates for claddings and many other non-bearing building structures. Biocarbon, also commonly known as Biochar, is a high-carbon, fine-grained solid that is produced through pyrolysis processes and currently mainly used for energy. Recently biocarbon has also gained attention for its potential value with in industrial applications such as composites (Giorcellia et al, 2018; Piri et.al, 2018). Addition of biocarbon in the biocomposites is likely to increase the UV-resistance and fire resistance of the materials and decrease hydrophilic nature of composites. Using biocarbon in polymer composites is also interesting because of its relatively low specific weight that will result to lighter composite materials. In this Building Light project the SMEs Torrgas and NPSP will collaborate with and Avans/CoE BBE in a feasibility study on the use of biocarbon in a NPSP biocomposite. The physicochemical properties and moisture absorption of the composites with biocarbon filler will be compared to the biocomposite obtained with the currently used calcium carbonate filler. These novel biocarbon-biocomposites are anticipated to have higher stability and lighter weight, hence resulting to a new, exciting building materials that will create new business opportunities for both of the SME partners.