I'm not sure if waste from building demolition is a good fit because of the potential for asbestos or other toxic waste. One possibility though might be waste wood from construction sites. That's clean wood that has the potential for a fairly orderly collection system. My town now collects wood from construction projects. That wood could be processed into wood flour and used as afeedstock for any WPC. There are a lot of really good ideas in this trhead.
I learned quite a bit from some of the projects that I designed. The one closest to this was a machine to process waste into landscaping timbers, which the process was to grind a mix of waste plastic and wood and then extrude it through a much smaller opening. It was a quite interesting project, partly because of the very high production rate, but also because the inventor could not provide a lot of information about the process.
For the material that you are describing, a much more tightly controlled process would be required, and probably one of a much smaller scale. The one I designed was sized to process at least 200 tons a day.
An interesting concept would be to utilize wood products from building demolition as feedstock, although it would not be practical, since the composite you describe would need a fairly pure and uniform feedstock. However,a different product for those much less demanding applications might be able to use the ground structural wood, and since it looks like quite a few of the problems that made the previous operation impractical have been solved, it might be worth a few minutes of thought.
j-allen...Thanks for the email..sounds like you have done some research...FibreTuff has improved performance, functionality and low price point versus other traditional WPC products. It was developed to replace various mineral or GFPP resins in certain applications..With the proper processing technigues you can replace 20 to 30% GFPP and lower part weight.. The strength of FibreTuff can reach 7,000 psi when traditional tested is performed.But because the material is isotropic compressible and very light, compared to GFPP which isnt compressible, orients glass fiber fibers in direction of flow...it is very hard to acheive comparable evaluation in standardized testing ..unless you process to make parts..Furthermore, the cellulose and or wood flour has a high amount or heat resistance compared to lower cellulosic products, ie plant based. except cotton i believe..There are different fiber structures in wood species...FibreTuff is mainly pine at this point based on various reasons, such as cost and processing....There are ways to make your fiber resource more stabile, have less odor and increase tensile strength and improve heat stability and still be competitive.....If you need more information please visit technology section on website or email through site...Thanks
Thanks for the question about the FibreTuff material...moisture has been reduced through the superior adhesion of the polyolefin and cellulose /wood flour in the pellet..high loaded natural fiber pellets will stay compacted and not swell easily.. The pellet also helps promote better adhesion in a part that can increase longevity of the product...improved CLTE. Processsing techniques will further improve resistance to moisture with a polymer rich surface...
This is very interesting, what we need now is information about durability, strenght, and surface finish. Also more information about the temperature handling capabilities.
Moisture is certainly a real problem in plastics molding, it has definitely rendered samples of other composites that I investigated unusable. Those were different enough that the only similarity was the wood fiber content. I mentioned the moisture concern as a point that does need more explanation. I would love to be able to design things using a wood0based composite that looked a bit like wood.
The problem with existing composites made from sawdust is strength and stability. Soldi hardwood has tensile strengths better than 10,000 PSI. (some hickory samples reach 20,000.) Even softwoods are good for 5000. What are the mechanical properties of this new composite? If it is comparable to real wood, then you have a winner, but if it costs half as much as wood but you need to use 3 times the cross section for the strength and rigidity, then it is not.
Around 1970 I worked on wood-plastic composites where we vacuum-pressure impregnated solid wood with a resin (polyester or acrylic) which we then polymerized in situ with ionizing radiation from an electron accelerator. The result was stronger than the wood and impervious to moisture. By irradiating the assembly after putting together the joinery, the excess resin bonded the joints. The final product had the appearance of finished wood.
We even achieved zonal hardening with, for example, a hard layer a few mm thick over softwood inside, or a tool handle hardened near the head yet lightweight for the rest of its length. Unfortunately, the process was not cheap so it was restricted to special applications, such as wooden legs which, thanks to the Viet Nam War, were in great demand at the time.
Hello Beth, Thanks for the question...My passion consumes 100% of my time and energy.....I have 6 yrs of college but do not have a formal 4 yr. engineering degree..learned by the school of hard knocks..repaired plastic machinery, compounded materials by trial and error. I have worked some ungodly hours, successfully started a machinery and compounding businesses. I am poor but not broke...but I love what I do...and love life's challenges.
Processors are always looking for ways to produce parts while staying on the green side of the business. This new material seems to have a lot of potential for throwaway packaging and other consumable designs. The price is comparable to higher end HDPE products and the strength properties seem to be right in the same ballpark.
Two new technologies from Stratasys, created in partnership with Boeing, Ford, and Siemens, will bring accurate, repeatable manufacturing of very large thermoplastic end products, and much bigger composite parts, onto the factory floor for industries including automotive and aerospace.
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