Manufacturing Wood-Plastic Composites and their Thermal Performance in Building Envelope

Abstract

Wood-plastic composites (WPCs) are becoming one of the most attractive materials in building envelopes. In addition to WPCs' architectural and design attraction, they can enhance the thermal performance of buildings by acting as insulation materials. The thermal performance of building materials requires new experimental methods that can simulate true indoor/outdoor temperatures. In this study, a simple quasi-steady heating film (QSHF) method is devised to measure the thermal conductivity of WPC samples utilizing blocks of standard materials with known thermal conductivity. QSHF device uses a 10cm×10cm×0.5mm silicon heating film controlled by a temperature regulator and several transparent acrylic square blocks of the same size with 10mm thickness as the standard materials along with various specially designed WPC samples for Kuwait. The WPC samples' top surface is considered the cold side of the system, which is open to indoor temperatures of 22 to 23 oC. The bottom layer is maintained at fixed temperatures ranging from 25 to 55 oC to simulate the outdoor temperatures of a hot subtropical desert environment like Kuwait. The thermal conductivity of several WPCs type namely FB16, FB18W, CD, and TD were obtained as 0.0912, 0.1174, 0.3453, and 0.3078 W/m.K, respectively. Experimental results for DP45-1 were not consistent at different temperatures. hence Multiphysics CFD simulation was conducted for DP45 which shows strong 2D effects. A typical building sample was also modelled in TRNSYS to compare cooling loads with and without WPC. Also, the limitations and advantages of using QSHF method are discussed.

A review on natural fiber composites: Polymer matrices, fiber surface treatments, fabrication methods, properties, and applications

“…The production method of extrusion is one that is frequently utilized and, on occasion, the preferred practical approach to the formation of complex thermoplastic profiles. The word “extrusion” comes from Greek origins that can be translated as “pushing out” or “squeezing.” 129 The main function of the extruder is to plasticize a polymer matrix and combine it with wood and other additives in line with the planned process 11 . A predefined flow of the resin mixture is sent from the hopper into the screw container.…”

“…The output of the extruder is often referred to as extrudate. Following the process of solidification, the extruded material undergoes termination and is then severed to achieve the desired dimensions 129 . The following four extrusion systems are capable of processing profiles: wood turner, corotating twin screw, counter‐rotating twin screw, and single screw.…”

“…A multilayered profile may be co‐extrusioned by a single screw extruder in the event that two extruders are not available. Composite materials are combined and pelletized using corotating or counter‐rotating double screw extruders 11,129 …”

“…Following the process of solidification, the extruded material undergoes termination and is then severed to achieve the desired dimensions. 129 The following four extrusion systems are capable of processing profiles: wood turner, corotating twin screw, counterrotating twin screw, and single screw. A multilayered profile may be co-extrusioned by a single screw extruder in the event that two extruders are not available.…”

“…The word "extrusion" comes from Greek origins that can be translated as "pushing out" or "squeezing." 129 The main function of the extruder is to plasticize a polymer matrix and combine it with wood and other additives…”