“Plastics are made by fools like me, but only God can make a tree”
I’ve always had a keen interest in the materials of Engineering and in recent years my interest has grown particularly with regard to Wood, as I have become somewhat of an amateur stickmaker.
While wood and timber have a wide range of uses, they are not suited to every application. Naturally, their use in any regulated industry is limited, but wood is the perfect “role model material” for engineers and material scientists seeking out the holy grail of biodegradable and renewable materials.
Such a benefit of wood is its high weight to strength ratio, which is comparable with mild steel (believe it or not).
For many years, mainstream thought has suggested that we are on the cusp of a revolution in materials used in Engineering and packaging etc. While there have been clear and measurable advances, the availability and application of these new materials has not had a transformative effect in the wider community or across different industries, with relatively high costs and low consumption rates symptomatic of new materials.
Wood and timber products are commonly available, cheap and effective. With this in mind, we can learn much from wood and its properties and it would be a shame to overlook its strengths.
Wood, if left exposed to the environment, will eventually degrade over time. However, simple treatments with preservatives, paints or varnishes, can prevent or slow the effects of the environment.
The Rise of PLGA
Enough talk about wood! Introducing another biodegradable material- PLGA. PLGA is not only biodegradable but is also a biocompatible copolymer that is used and approved for use in regulated industries such as the medical device industry. It has many applications including fracture fixation and in recent years has been used to manufacture biodegradable stents. The key process allowing PLGA to degrade is throughHydrolysis which occurs in the presence of water. This biodegrading and resorption property makes it a very attractive material, simply using the chemistry and physiology of the body to start the process. We spoke of wood treatments with paints or varnish, similarly, PLGA implants can be coated in order to provide therapeutic drugs or it can be coated to control the rate of degradation, particularly in the early stages of use.
As with many biodegradable materials, PLGA is expensive and therefore it is not commonly used other than in medical devices. However, if in time, these materials can be made more cost friendly, it could open up the possibilities of wider applications.
The Future
It will be difficult for materials such as PLGA to ever reach the consumption rates like wood or timber, nor is the need likely, but increasingly material scientists look to nature in order to inspire or inform their next advancements. If you are interested in material science, I recommend reading the classic book by J.E Gordon, “The New Science of Strong materials (or why you don’t fall through the floor.) In his final chapter, entitled, “The materials of the future” he oddly offers little insight, asserting that speculation only offers a receipe in “how to guess incorrecty” . On this note, I too will refrain from further speculation.
Comments
Post has no comments.