scholarly journals Hydrophobic and Anti-Icing Behavior of UV-Laser-Treated Polyester Resin-Based Gelcoats

Processes ◽  
2020 ◽  
Vol 8 (12) ◽  
pp. 1642
Author(s):  
Rafał Kozera ◽  
Bartłomiej Przybyszewski ◽  
Zuzanna D. Krawczyk ◽  
Anna Boczkowska ◽  
Bogna Sztorch ◽  
...  
Keyword(s):  
Contact Angle ◽  
Polyester Resin ◽  
Unsaturated Polyester ◽  
Contact Angle Hysteresis ◽  
Unsaturated Polyester Resin ◽  
Water Repellent ◽  
Chemical Modifiers ◽  
Static Contact ◽  
The Impact ◽  
Hybrid Modification

Ice accumulation on wind turbine blades due to the impact of supercooled water droplets can be reduced by the application of surfaces with anti-icing properties. Hydrophobic surfaces are considered as a promising solution because of their water repellent behavior. In recent years, short-pulsed laser technologies have been developed as an efficient technique to modify the surface properties of materials. However, the anti-icing properties of such surfaces have not yet been validated. In this work, a hybrid modification of polyester resin-based gelcoats was adopted. Laser patterning (LP) was used to produce periodic surface structures on modified unsaturated polyester resin (UPR) substrates. One of the innovations of this research is the utilization of novel purpose-made chemical modifiers for gelcoats. The implementation of linear polymethylhydrosiloxane (PMHS) as a building block is a key improvement in terms of durability and functionality of the coating, since there is an option of introducing not only groups bonding in the polyester into one molecule, but also groups that increase hydrophobicity. The other novelty is a successfully conducted experiment combining such chemical modification with laser texturization of the surface. The influence of the laser energy, pattern shape, and spatial periods on the topographical characteristics and hydrophobicity as well as the anti-icing properties of the produced surfaces were investigated. To characterize the surface topography of the produced structures, scanning electron microscopy (SEM) and profilometer were utilized. Measurements of the wettability parameters (static contact angle and contact angle hysteresis) on the treated surfaces allowed the identification of the influence of wetting behavior and laser parameters on the investigated materials. Anti-icing properties were characterized by ice adhesion (IA) and freezing delay time (FDT) tests. It was found that hybrid modification of unsaturated polyester resin by chemical modifiers and laser treatment increased the hydrophobic and anti-icing properties of polyester gelcoats.

scholarly journals Hybrid Modification of Unsaturated Polyester Resins to Obtain Hydro- and Icephobic Properties

Processes ◽  
2020 ◽  
Vol 8 (12) ◽  
pp. 1635
Author(s):  
Rafał Kozera ◽  
Bartłomiej Przybyszewski ◽  
Katarzyna Żołyńska ◽  
Anna Boczkowska ◽  
Bogna Sztorch ◽  
...  
Keyword(s):  
Contact Angle ◽  
Composite Structures ◽  
Unsaturated Polyester ◽  
Contact Angle Hysteresis ◽  
Point Of View ◽  
Polyhedral Oligomeric Silsesquioxanes ◽  
Adhesion Forces ◽  
Ice Accumulation ◽  
Hybrid Modification ◽  
Ice Adhesion

Ice accumulation is a key and unsolved problem for many composite structures with polymer matrices, e.g., wind turbines and airplanes. One of the solutions to avoid icing is to use anti-icing coatings. In recent years, the influence of hydrophobicity of a surface on its icephobic properties has been studied. This solution is based on the idea that a material with poor wettability maximally reduces the contact time between a cooled drop of water and the surface, consequently prevents the formation of ice, and decreases its adhesion to the surface. In this work, a hybrid modification of a gelcoat based on unsaturated polyester resin with nanosilica and chemical modifiers from the group of triple functionalized polyhedral oligomeric silsesquioxanes (POSS) and double organofunctionalized polysiloxanes (generally called multi-functionalized organosilicon compounds (MFSC)) was applied. The work describes how the change of modifier concentration and its structural structure finally influences the ice phobic properties. The modifiers used in their structure groups lowered the free surface energy and crosslinking groups with the applied resin, lowering the phenomena of migration and removing the modifier from the surface layer of gelcoat. The main studies from the icephobicity point of view were the measurements of ice adhesion forces between modified materials and ice. The tests were based on the measurements of the shear strength between the ice layer and the modified surface and were conducted using a tensile machine. Hydrophobic properties of the obtained nanocomposites were determined by measurement of the contact angle and contact angle hysteresis. As the results of the work, it was found that the modification of gelcoat with nanosilica and multi-functionalized silicone compounds results in the improvement of icephobic properties when compared to unmodified gelcoat while no direct influence of wettability properties was found. Ice adhesion decreased by more than 30%.

scholarly journals Experimental Evaluation of the Curing of Unsaturated Polyester Resin at Various Amounts of Methyl Ethyl Ketone Peroxide, Cobalt Octoate and Porcelain Powder

2020 ◽  
Vol 71 (10) ◽  
pp. 58-66
Author(s):  
Mohamed Farsane ◽  
Lhasnaoui Soufia ◽  
Abdellah Anouar ◽  
Souad Chah ◽  
Said Dagdag ◽  
...  
Keyword(s):  
Methyl Ethyl Ketone ◽  
Experimental Evaluation ◽  
Polyester Resin ◽  
Unsaturated Polyester ◽  
Unsaturated Polyester Resin ◽  
Time Range ◽  
Curing Process ◽  
Methyl Ethyl Ketone Peroxide ◽  
Methyl Ethyl ◽  
The Impact

The goal of this research is to investigate the impact of the three parameters on the cure of the unsaturated polyester resin. The obtained values show the influence of each parameter on the cure and hence enables to establish a time-range with regard of the percentage of the components for a good management of the curing process.

scholarly journals Effect of Al2O3 on the Tensile and Impact Strength of Flax/Unsaturated Polyester Composite with Emphasis on Automobile Body Applications

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Gebre Fenta Aynalem ◽  
Belete Sirahbizu
Keyword(s):  
Impact Strength ◽  
Polyester Resin ◽  
Natural Fiber ◽  
Resin Composite ◽  
Unsaturated Polyester ◽  
Fiber Material ◽  
Strength Properties ◽  
Unsaturated Polyester Resin ◽  
Molding Process ◽  
The Impact

This study has endeavored to develop an Al2O3-filled natural fiber reinforced polymer composite which is intended to substitute the most widely used synthetic E-glass fiber material. To attain the desired objective of the work, 0, 5, 10, and 15 wt% Al2O3-filled chopped flax/unsaturated polyester resin composite have been developed by the conventional hand-lay-up method followed by a compression molding process. Consequently, characterization and mechanical property tests are conducted based on the ASTM standard. The results revealed that both tensile and impact strength properties of the base chopped flax/unsaturated polyester resin composite are all affected due to the inclusion and variation of the content of Al2O3 in 15 and 25 wt% fiber loading cases. It has been noticed that a 39.06% increase in the ultimate tensile strength of the composite in 25/UPR-5 composition has been gained. The effect of Al2O3 on the impact strength of the base composite has also been analyzed and a 45% increase has been observed in 15/UPR-10 composition. The findings also witnessed that the newly developed composite can be applied to make automotive parts such as mud guard and engine undercover.

Micro-, nano- and hierarchical structures for superhydrophobicity, self-cleaning and low adhesion

2009 ◽  
Vol 367 (1894) ◽  
pp. 1631-1672 ◽  
Author(s):  
Bharat Bhushan ◽  
Yong Chae Jung ◽  
Kerstin Koch
Keyword(s):  
Contact Angle ◽  
Low Cost ◽  
Contact Angle Hysteresis ◽  
Hierarchical Structures ◽  
Adhesive Force ◽  
Water Repellent ◽  
Lotus Effect ◽  
Composite State ◽  
Static Contact ◽  
Self Cleaning

Superhydrophobic surfaces exhibit extreme water-repellent properties. These surfaces with high contact angle and low contact angle hysteresis also exhibit a self-cleaning effect and low drag for fluid flow. Certain plant leaves, such as lotus leaves, are known to be superhydrophobic and self-cleaning due to the hierarchical roughness of their leaf surfaces. The self-cleaning phenomenon is widely known as the ‘lotus effect’. Superhydrophobic and self-cleaning surfaces can be produced by using roughness combined with hydrophobic coatings. In this paper, the effect of micro- and nanopatterned polymers on hydrophobicity is reviewed. Silicon surfaces patterned with pillars and deposited with a hydrophobic coating were studied to demonstrate how the effects of pitch value, droplet size and impact velocity influence the transition from a composite state to a wetted state. In order to fabricate hierarchical structures, a low-cost and flexible technique that involves replication of microstructures and self-assembly of hydrophobic waxes is described. The influence of micro-, nano- and hierarchical structures on superhydrophobicity is discussed by the investigation of static contact angle, contact angle hysteresis, droplet evaporation and propensity for air pocket formation. In addition, their influence on adhesive force as well as efficiency of self-cleaning is discussed.

Sign in / Sign up

Export Citation Format

Share Document