Exterior Applications Research Articles

Randomly Oriented Strand Board Composites from Nanoengineered Protein-Based Wood Adhesive

A nanoengineered canola protein adhesive (CPA) with improved adhesion and water resistance was previously developed by chemically modifying canola protein with ammonium persulfate followed by exfoliating graphite oxide nanoparticles. The objectives of this research were to prepare randomly oriented strand board (ROSB) composites using nanoengineered canola protein adhesive at pilot scale and to characterize the adhesive and mechanical properties of ROSB panels. Six groups of ROSB panels were produced by replacing commercial liquid phenol formaldehyde (LPF) with CPA at levels of 0%, 20%, 40%, 60%, 80%, and 100%. The mechanical and water resistance properties were tested according to ASTM D1037-12 and CSA O437.0-93 standard specifications. The mechanical performances, bond durability, and water resistance were not affected by CPA addition up to a level of 40%, compared to commercial LPF adhesives. Mechanical performance of all ROSB panels prepared in this study exceeded the acceptable minimum standards specified by CSA O437.0-93 standards. Canola-based adhesive can be used in commercial ROSB production, either as 100% resin for interior application or up to 40% replacement of LPF for exterior application.

The Weathering Study of PC/ASA Alloy For Automotive Exterior Applications

Polycarbonates (PC) are used in automotive industry due to high physical and mechanical properties like high impact resistance and ductility. Polycarbonates are blended with ABS (Acrylonitrile-Butadiene-Styrene) and ASA (Acrylonitrile-Styrene-Acrylate) terpolymers for interior and exterior applications of automotive components to achieve good physical and mechanical properties. Other reason for choosing such alloys for interior applications is the IZOD impact resistance requirement higher than 40kJ/m 2 . Recently, grades of PC/ASA with UV stabilized are developed for non-painted exterior applications. The aim of our study is to investigate whether new developed PC/ASA could be chosen for exterior applications of automotive industry. In this study, the samples are prepared from injection molding and the weathering performance of PC/ASA was tested by a weather-o-meter for 1500h at a total of 1890 kJ/m 2 at 340nm with a cut-off filter at λ<290nm. The results are evaluated by FT-IR, DSC, TGA and SEM. It has been observed that UV degradation of PC/ASA leads to several major changes in its IR spectrum like broad bands occurred in the hydroxyl region around 3300cm -1 , and carbonyl stretching region increased around 1728 cm -1 . The main degradations were based on photo-oxidation and photo-Fries rearrangement of PC. In our study, the photo-oxidation was followed by the color shift to yellowing of the polymer.

Water absorption and mold susceptibility of wood flour/polypropylene composites modified with silane‐wax emulsions

Wood plastic composites can absorb water in exterior applications due to the hygroscopicity of wood flour (WF). The cycle of adsorption and desorption process causes damage to the interfacial bonding between WF and polymer matrix, which benefits the fungal attack. In this study, WF was, respectively, immersed with silane, wax emulsion, and their compound systems for modification at different concentrations (1, 2, and 4%, respectively). Then, the modified WF was mixed with polypropylene (PP) to produce WF/PP composites at mass ratio of 6:4. The water absorption and mold susceptibility of the composites against Aspergillus niger were investigated. The results showed that silane can improve the interfacial adhesion between WF and PP. The water uptake of WF/PP composites treated with 4% silane decreased by 6% compared with the control, and the average mold growth rating decreased from level 4 (mold covering of 75–100%) to level 1 (mold covering of 0–25%). The strong hydrophobicity of wax had a negative effect on the interfacial adhesion of the composites. Thus, composites modified with wax and silane‐wax compounds showed higher water uptake than the control. However, the mold resistance of composites was improved in these groups. POLYM. COMPOS., 40:141–148, 2019. © 2017 Society of Plastics Engineers

Development and characterization of retro-reflective colored tiles for advanced building skins

RR materials, able to reflect the solar radiation mainly toward the incident direction, are a strategy to mitigate the Urban Heat Island (UHI) phenomenon, by reducing the heat trapped inside the urban canyon.This paper introduces new ceramic tiles for outdoor applications properly treated to get RR optic properties.Traditional colored tiles were covered with a UV resistant, transparent paint containing RR microspheres for exterior applications, through an ad-hoc continuous tape casting process, developed for this specific application. The goal is to produce RR tiles through industrial continuous process in order to ensure the penetration of such innovative building materials in the market.Three types of microspheres were tested: i) clear barium titanate glass microspheres; ii) hemispherically aluminum coated barium titanate glass microspheres; iii) hemispherically aluminum coated barium titanate glass microspheres with an additional fluoropolymer coating. The obtained tiles were investigated with a spectrophotometric analysis, a study of the spatial distribution of the reflected radiation, a colorimetric analysis to evaluate changes in tiles’ original color. Reflectance is increased by clear barium titanate glass microspheres, while is almost halved by aluminum-coated spheres. All the three types of microspheres provide strong RR behavior for incident light directions from 0° to 60° with respect to the surface normal. Nevertheless, the aluminum-coated microspheres change completely the tiles’ original color, making the application of the aluminum RR tiles very limited. Clear barium microspheres instead improve the optic properties of the original tiles, with negligible effects on the color.

Durability of the reaction to fire performance of fire-retardant-treated wood products in exterior applications – a 10-year report

ABSTRACTFire retardants may considerably improve the reaction to fire properties of wood products, but the long term durabi­lity needs to be addressed. Several long term studies of fire retardant treated (FRT) wood products over time are presented. They are performed according to a European system based on earlier Nordic and North American systems and include accelerated aging according to different procedures and natural weathering up to 10 years. Main conclusions are:• products studied and used commercially• The reaction to fire properties of FRT wood may be maintained after accelerated and natural aging if the The hygroscopic properties are unchanged compared to untreated wood for most FRT wood retention levels are high enough, but several products lose most of their improved reaction to fire properties during weathering• Paint systems contribute considerably to weather protection and are usually needed to maintain the reaction to fire performance at exterior applications

Thermally modified Scots pine and Norway spruce wood as substrate for coating systems

Thermally modified wood (TMW) is increasingly used in exterior applications as an alternative to tropical hardwoods or wood impregnated with biocides. Despite its enhanced biological durability and dimensional stability, a surface treatment of TMW with coating systems can be required in certain applications. This study assessed material characteristics of Norway spruce and Scots pine wood that was thermally modified according to the ThermoWood® process and their effect on the performance of commercially available coating systems: a solventborne oil, a waterborne alkyd-reinforced acrylate paint and a waterborne acrylate paint. Residual extractives and remaining degradation products found in TMW, carry the risk of causing discoloration or of interfering with the curing reactions of coating systems. The penetration of coating systems into TMW was not found to differ from unmodified wood, although an excessive penetration of solventborne oil was found occasionally for TMW. The adhesion strength of waterborne coatings depended on the system that was used. While one system performed sufficiently on TMW, the other coating systems showed a considerable reduction in adhesion strength already after a mild treatment (<200°C). This reduction could not be attributed to the increase in hydrophobicity of TMW that was evident from contact angle measurements, but was rather related to the mechanical interaction of the specific substrate/coating system.

Reaction mechanisms inhibiting the release of aqueous extracts from merbau heartwood by iron(II) and copper(II)

Extractive bleeding with adjacent staining from merbau heartwood is a problem affecting exterior applications. Although the inhibition method of the exudate has been performed via complexation of the aqueous extracts (AE) and iron/copper ions, its mechanisms remain unclear. The aim of this study is to clarify the complexation mechanisms of AE with iron/copper ions. The results obtained from both 13C NMR and FTIR analyses show that the primary component of AE is catechin-/epicatechin-based condensed tannin. Further results of the complexation test under heating conditions revealed that the catechol units in condensed tannin of AE could efficiently complex iron ion, forming the bis-bidentate complex, leading to decreased water solubility of AE. However, AE could not complex copper ion to form the insoluble AE–Cu complex directly at ambient temperature, and it relied on the o-quinone, which was derived from the heated AE at 100 °C, complexed with copper ion to form the bis-bidentate complexes.

Flexural Properties of PVC/Bamboo Composites under Static and Dynamic-Thermal Conditions: Effects of Composition and Water Absorption

Polyvinyl chloride (PVC)/bamboo composites have been prepared and assessed for their use in interior and exterior load-bearing applications. PVC composites were formed by compounding PVC with different bamboo particle sizes and loadings. The mechanical properties of these composites were determined at both ambient and elevated temperatures and after long-term water soaking. Analysis revealed that bamboo incorporation improved the PVC composite flexural modulus which was also observed with dynamic mechanical-thermal analysis on heating composites toca.70°C. Addition of 25% and 50% bamboo particles increases flexural modulus by 80% with dependency on whether fine (&lt;75 μm) or coarse (&lt;1 mm) particles were used. On water soaking to saturation, composites had water weight uptakes of 10%, with reduced flexural properties obtained for all water-soaked composites. Nonetheless, the results of this study show that PVC/bamboo composites achieve the minimum flexural performance of ASTM D 6662, indicating potential for their use in exterior applications.

Improvement of thermodynamic efficiency of the humid biofuel application in the distributed generation power suppliers

The problems of the humid biofuel application in the distributed energy engineering facilities are considered. Use of drying (and thermal proceeding) in energy saving makes it possible to perform efficient biofuel gasification, compensating for, in many cases, the negative influence of the moisture on the efficiency of the energy facilities. The complicated functional connection between the drying and the gasification processes as well as of the gasification product purification are analyzed. The cold purification, taken as the basic technology, reduces the efficiency of the gasification versions with the temperature above the level of the liquid slag removal; yet, if the temperature is not higher than the ash softening beginning, then this influence is insufficient. When compared, the efficiency of the STIG steam-gas facility on the humid fuel tends to be just a little lower than the dry fuel and reaches 45–49%. The calculations show that, at the low gasification temperature, we should not remove all the fuel moisture if the humidity is below 40%. The oxygen blast application in the gasifier reduces the efficiency to some extent but oxygen is necessary to accumulate the highenergy synthetic gas, in particular, for the peak or the exterior application.

Specie – treatment - adhesive combinations for glulam purpose

Glued laminated timber is an engineered product that requires precision manufacturing in all its stages. The finished product can only be tested in laboratory conditions. However, it is necessary to have quality control in the production to ensure that the properties of the glulam are appropriate to the product specified requirements in accordance with the standards. In Brazil is still no specific standard of qualification for the manufactures of Glulam. In this context, different kinds of wood, adhesives and preservative treatments in the composition of Glulam can be used. This paper aims to evaluate the proposed trials conducted with combinations of four Brazilian reforestation species, three adhesives and three types of preservative treatment. As a result was observed that combinations, which showed the best performance, were pine and parica wood, with any type of adhesive or treatment investigated, which can be used in exterior applications. Lyptus ® wood for any combination of treatments falls into the internal use class. Teak wood can be used indoors (adhesive polyurethane and all kinds of treatment) or external (phenol resorcinol formaldehyde adhesive and all kinds of treatment).

Sensitivity of waterborne coating materials to high acidity and high content of arabinogalactan in larch heartwood

Abstract Larch wood is known to be a challenging substrate for waterborne coatings on windows or claddings in exterior applications. In earlier studies the surface properties of larch heartwood were characterised with low pH-values and high content of arabinogalactan. A systematic variation of formulations with different combinations of binders and thickening additives was investigated regarding the sensitivity of the coating materials to high acidity and arabinogalactan. Panels of spruce wood were treated with low-pH buffer solutions and arabinogalactan solutions and after drying the coating materials were applied by spraying. Acetic acid and arabinogalactan solutions were added stepwise to wet samples of coating materials while pH-values and viscosity were measured. Different buffer capacities, changes in viscosity and qualities of film formation were observed depending on coating formulation. The selection of binder and thickening additives enables the formulation of coating materials with lower sensitivity to specific surface properties of larch wood and thus higher quality.

Strength properties and natural durability of Avocado (Persea americana Mill.) branch wood

This paper reports on mechanical properties and natural durability of avocado branch wood (Persea americana Mill.) with the objectives of providing a reliable property profile and to promote the rational use of this abundant yet largely neglected natural resource. The mechanical properties (static bending, compression, shear, impact bending) and hardness were determined in accordance with European standards (CEN). Natural durability was assessed according to the European standard EN 350-1 (agar block test) using the white rot fungi Trametes versicolor and Phanerochaete chrysosporium, and the brown rot fungus Postia placenta. Avocado trees yield a low to medium density (0,44-0,54-0,64 g/cm3 at 12% mc) branch wood with below average strength under static bending, compression and tension parallel to the grain and average values for longitudinal shear, impact bending and hardness. The wood is rated non-resistant (class 5 according to EN 350-1) and thus is not suitable for exterior applications unless treated. Considering its property profile and the small dimensions available, avocado wood is recommended for general carpentry, furniture, interior paneling, glue-boards for closets and cabinets, and glue-lams for indoor framework.

Bonding Strength of Some Adhesives in Heat-Treated Hornbeam (Carpinus betulus L.) Wood Used for Interior and Exterior Decoration

Heat-treated wood has an ever-expanding market for exterior and interior applications. The objective of this study was to determine the effect of a heat treatment on the bonding strength of hornbeam (Carpinus betulus L.) wood that was bonded with melamine formaldehyde (MF), polyurethane (PUR), and polyvinyl acetate (PVAc-D4) adhesives. Hornbeam lamellas were heat treated at 150 °C, 175 °C, 200 °C, and 225 °C for 3 h and then bonded. The bonding strength of the specimens was determined. In addition, the density, weight loss, and pH value of the heat-treated wood were investigated. The results showed that the bonding strengths of the heat-treated wood specimens decreased with the temperature of the heat treatment. The bonding strength of the PUR adhesive was higher than the MF and the PVAc-D4.

Mechanical Properties and Structure of Novel Polymer Blends and Composites Fabricated by Reactive and High-shear Rotational Processing

Various polymer alloys have been examined to achieve performance beyond that of single polymers. Polyamide 6 (PA6) has extraordinary mechanical properties, impact absorbability, and high heat resistance necessary for exterior and interior automotive applications. Nevertheless, some materials and their combinations can exhibit inferior physical properties. This paper describes a novel polymer blend with PA6, fabricated using high-shear rotational processing. Modulated differential scanning calorimetry (M-DSC), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) elucidated thermal properties and morphologies of PA6 blends. Tensile and Izod tests revealed their mechanical properties. Results show that novel PA6 blends are useful for automotive applications.

Assessment of the European Standard for the determination of resistance of marble to thermal and moisture cycles: recommendations for improvements

The bowing phenomenon is so relevant that two projects, EU funded, from 1999 studied it and a European Standard to assess the resistance to thermal and moisture cycles (influencing bowing) has been recently adopted. In particular, according EN 16306: 2013, measurements of bowing and flexural strength should be performed before and at the end of the ageing cycles. Additional non-destructive tests are recommended, but are not compulsory for the standard. Moreover, Annex A of EN 16306 contains guidance on the limit values for the selection of marble types suitable for outdoor uses, especially facade applications. Eleven varieties of marble have been tested by means of this laboratory ageing test. Non-destructive tests such as the measurements of ultrasonic pulse velocity (UPV), adjacent grains analysis, open porosity, and water absorption have been executed together with the conventional flexural strength test. The results obtained from image analysis on thin sections indicate that the AGA index may not always be correlated with the other tests: amount of bowing, loss of flexural strength, or loss of UPV. Some consideration of the decrease in mechanical resistance and the bowing in relation to the variety of marble tested and the limit values indicated in Annex A of EN 16306 can be noted. It is known that bowing and rapid strength loss occur in some varieties of marble when used as exterior cladding and other exterior applications. Additional conclusions have been drawn: bowing and flexural strength correlate well and can be used to assess the suitability of the marble to be employed in outdoors.

Effect of nanoclay and silica on mechanical and morphological properties of jute cellulose polyethylene biocomposites

In this study, jute cellulose/polyethylene (PE) biocomposites were prepared using a hot press machine. Silica and nanoclay act as reinforcing agents in the composite system. The effects of clay and silica addition on the mechanical, thermal, and morphological properties of jute cellulose/PE biocomposites with different fiber loadings (5, 10, 15, and 20 wt %) were investigated. The biocomposites were characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy, and thermogravimetric analysis. The mechanical properties were investigated using a universal testing machine. From FTIR results, it indicates that the CO stretching vibration had disappeared, while the intensity of peaks at 1718 and 1716 cm−1 appeared after addition of silica. The better interfacial bonding between jute cellulose/PE/silica biocomposites are reflected in the enhancement of the mechanical properties as well as thermal stability. The tensile strength and modulus had shown the highest values as well as higher activation energy for thermal decomposition. The surface area analysis result showed that the jute cellulose/PE/silica biocomposites have higher surface area and pore volume with less pore size. The manufactured biocomposites can be used in interior and exterior applications as well as a construction material. J. VINYL ADDIT. TECHNOL., 23:E113–E118, 2017. © 2016 Society of Plastics Engineers

Durability of the reaction to fire performance for fire retardant treated (FRT) wood products in exterior applications – a ten years report

Several long term experimental studies on the maintained reaction to fire performance of fire retardant treated (FRT) wood products over time are presented. They are performed according to a European system based on earlier Nordic and North American systems and include accelerated ageing according to different procedures and natural weathering up to ten years. Main conclusions are: The hygroscopic properties are unchanged compared to untreated wood for most FRT wood products used commercially. The reaction to fire properties of FRT wood may be maintained after accelerated and natural ageing if the retention levels are high enough, but several FRT wood products loose most of their improved reaction to fire properties during weathering. Paint systems contribute considerably to maintain of the fire performance at exterior application and are usually needed to maintain the fire performance after weathering.

Photodegradation of thermally-modified Scots pine and Norway spruce investigated on thin micro-veneers

The exposure to ultraviolet light results in surface photodegradation of uncoated wood during exterior application. When using thermally-modified wood in exterior applications, chemical changes that occur during the modification process might affect a subsequent photodegradation. This study investigates the impact of artificial weathering on the photodegradation of thin micro-veneers of thermally-modified Scots pine and Norway spruce by means of FT-IR spectroscopy and micro-tensile strength testing. FT-IR spectra revealed photodegradation reactions of lignin that resulted in the disappearance of the peak at 1508 cm−1 after 144 h, irrespective of the thermal modification process. Loss in micro-tensile strength by photodegradation was higher for finite- than for zero-span micro tensile strength as a result of the loss of amorphous carbohydrates. Although strength loss of unweathered veneers was evident for thermally modified wood, the rate at which strength loss occurs during artificial weathering was considerably decreased by the thermal modification process. It was concluded that the amorphous carbohydrates were less degraded during artificial weathering as they were already pre-degraded during the thermal modification process.

Effects of cryogenic thermal cycle and immersion on the mechanical characteristics of phenol-resin bonded plywood

The main objective of the present study is to investigate the performance degradation of the plywood used in a liquefied natural gas (LNG) cargo containment system (CCS). A plywood sheet features an odd number of thinly layered wooden plies bonded perpendicularly to the previous layer to give it a very strong and durable structure. Owing to this strong point, plywood is applied to a variety of interior and exterior applications. Above all, it is widely adopted as insulation panels in an LNG CCS owing to a high stiffness with low density and its superior mechanical capabilities. As an insulation material of an LNG CCS, plywood is constantly exposed to repeated wave-induced thermal variations caused by the loading (−163°C) and unloading (20°C) of LNG during general operating periods of 25years on average. Therefore, the effects of cryogenic-level thermal loads on the material characteristics of plywood must be analyzed with respect to the design and safety aspects of LNG CCSs. In the present study, the influences of the estimated thermal load, testing temperature, and grain orientation on plywood adopted in an LNG CCS are investigated. In terms of safety and design, the repeated thermal loads in a LNG CCS must be considered because the modulus of elasticity (MOE), tensile strength (TS), and modulus of rupture (MOR) are degraded by thermal treatments, such as cyclic thermal-shock and cryogenic immersion.

English

Tiles are durable and have a long lifespan. They may be used as a floor finish for both interior and exterior applications. Experimental and field studies were conducted to investigate the parameters and properties of terrazzo tiles from different regions, namely Erbil and Koya being represented by factories (A) and (B) respectively. These parameters and properties are dimensions, water absorption, modulus of rupture and impact resistance. Test results indicate that the dimensions and modulus of rupture for the tiles from both factories (A) and (B) are conformable with Iraqi specifications, but water absorption of terrazzo tiles from factory (B) does not conform with the Iraqi specification and having surface and total absorption values which are 55.1% and 23.8% higher than that for factory (A) tiles, respectively. The results show that terrazzo tiles of factory (A) have an impact resistance value which is 50% higher than that of tiles from factory (B). The field study which includes questionnaire procedure indicates that 63% of the residents agreed that the terrazzo tiles are beautiful as a floor finishing material and at the same time 94% agreed that this material is expensive. This study shows also that only 20% of Koya residents are satisfied with the quality of the production of factory (B), whereas, 90% of Erbil residents are satisfied with the production of factory (A).