Are bioplastics better than fossil-fuel based ones?

that's fair enough that's one subset of plastics and we're talking specifically about bioplastic so I have like kind of a noob question cuz I know so little about this I assume a bioplastic is something that is made from microbes or from a biological material like cellulose from plants is that right though yeah generally so bioplastic just means a plastic that's made from a biological resource so cellulose is a common like raw material that's used for making bioplastics but there are other

ways of making it so for like some of the traditional Plastics that are derived from like alcohols um you can just use a bio alcohol version rather than the actual fossil fuel version of the alcohol now I'm going through a whole how do you get alcohol from oil that comes out the ground I mean they're all carbon containing things feel like I'm getting a bit distracted with the whole alcohol thing though this seems like a separate episode yeah it does let's rewind so uh yeah basically a

bioplastic is a plastic material that's just made from biological resources yeah and cellulose basically comes from Plants right yeah it's not the thing I tend to think of is plastic like polyethylene say or PVC which is what you tend to think of when you think of plastics but I guess that's probably because it it comes from a biological source that we wouldn't have tended to have used as much yeah a lot of this comes about because of essentially the oil industry right what

do plastics all come from the oil industry yeah that's kind of my kind of like newbie understanding of it is someone who's just kind of read about this stuff in popular culture that basically the oil industry got huge and then we were able to make loads of plastics that were really cheap I mean that's partly true we kind of have Plastics of other kind not just synthetic Plastics made from fossil fuels but we also have some natural Plastics like rubber um which is from a

tree I mean what defines a polymer from a plastic or sorry a plastic from a polymer I think this is what in the last episode we just defined it as a hydrocarbon for Simplicity but you can have a material that has plastic properties right which kind of refers to how it stretches or bends or deforms so I don't think we ever really got to the bottom of it I think we just sort of said hydrocarbons okay so um according to the internet Plastics are polymers but not all polymers are plastic so

Plastics are a subset of polymers okay specifically long chains of polymers that's not a very helpful definition so anyway yeah so if we sort of come from this idea that most of the Plastics that we use today are synthetic and come from the oil industry will assume that and that's kind of a motivation for researching bioplastics right so instead of relying on this finite resource would have a renewable way of creating them yeah that's one of the mo motivations

another motivation is just to create Plastics that are more biodegradable cuz all Plastics will biodegrade but it's just with the fossil fuel based they'll take years and sometimes decades to biodegrade whereas with the bioplastics they should in theory biodegrade over a much shorter time frame so like a few days oh okay I would assume if you're making a plastic like take I think polyethylene is one of the simplest ones yeah it doesn't really matter how you've

made it whether it's a biological Source or not it'll still have the same properties so it will'll still take the same amount of time to break down so like I think the motivation to have more bio biodegradable plastic is more reflective of like what the current market use of bioplastics are big chunk is used for um food packaging so like food packaging that can be bio that is biodegradable okay so essentially the single use Plastics would be almost like a I guess a lower value CU they don't

need to persist for long they have one use for I don't know a few months probably yeah yeah I definitely think there's like a camp of bioplastics that kind of Encompass different environmental issues that we're trying to address one is reducing fossil fuel dependency and then another reducing plastic persisting in our environment so we've got to like talk about bioplastics and biodegradable Plastics as separate things and I guess this kind of gets me thinking about if

we're talking about the oil industry which is I guess a fairly new industry she says knowing nothing I guess it it makes me wonder like so when were biop Plastics first produced or first discovered or when was the process first created do you guys know anything about that yeah so I'm pretty sure bioplastics predate fossil fuel based Plastics just because like in the 1800s we didn't really have oiling gas so there you to use like biomass materials over for that yeah so I was

reading that um our first plastic was actually latex and rubber from, 1500 BCE by the uh miso American cultures they were using this for making containers and making water resistant clothing oh do do you know kind of how they process it because I know that rubber does come from plants but I've never really thought about how you'd actually use it I could imagine they just take some plant fibers and weave them or knit them and that would be it but but again totally ignorant here no idea I can't

remember how rubber is made but I do know like latex and rubber is tapped out of a tree so sort of like maple syrup you kind of have the right kind of tree and the core has liquid in so it's like mining for plastic out of a tree but again I guess because you're relying on a natural resource it takes time to harvest it so if you're moving to more modern processing method methods it's probably more efficient to just make it yourself which might be why I tend to think of it as being the thing

that comes from the oil industry and it's all synthetic and that's it that's the ironic thing about fossil fuels it is faster but it's also not faster it's faster because we can just dig out fossil fuels but they took millions of years to form first or are you thinking of the actual once we've got the oil the process then yes so literally once people get it out the ground because it at one point it was so abundant that it it sounds like from what I know that

people was using it all the time are we talking about rubber or we talking about normal plastic now Plastics in general I suppose yeah Plastics these days um the synthetic kind are made fairly quickly we have a well established industrial processes for that polymerization is the key stage it is Plastics but you kind of have you don't just get oil and polarize it you have to break it down to the monomers first yeah that involves cracking yes and then polymerization yes

yeah okay so I remember fractional distillation from when I was in school is that what you mean by breaking it into the monomers and then you can do what you want with it that's like a sorting process yeah so you're sorting it by size of the hydrocarbon chain and then you break the chains into smaller components and then you stick them back together but in a particular way so you get the plastic that you want instead of liquid hydrocarbon yeah uh so fractional dissol is like separating off like

different um I guess chemicals if you have a mixture mhm cracking is similar but cracking is more you have a chemical or a chain but you want to break it down into smaller chains so that would be the difference fair enough I get it so I'm building up this picture that we have Plastics from a biological origin like rubber that have existed for longer than Plastics like polyethylene that are generally made synthetically yeah so what percentage of Plastics in used

today have a biological Source do you know it's uh currently less than 1% it's around 0.6% primarily due to what Plastics are used for some some people may not be aware but like basically Plastics and everything we went into some of this from the Plastics episode like I looked around the room and was like the pipes that go to my central heating radiator and I'm looking around some more the cables that come from my computer yep all plastic yeah so we talked in the

last episode about Plastics about the common ones which I keep mentioning but what about common bioplastics what are some of those yeah so the types of common bioplastics differ quite a bit from the most common conventional bioplastics and that's just due to what bioplastics are being used for mostly so most bioplastics are the starch based Plastics or they can be what a plastic that's known as pla which stands for polylactic acid they account for around 40% of the current bioplastics market

but you'd also have like bio versions of like P or or PE but they're like much smaller fractions of the current bioplastic market okay so the common ones I was thinking of the polyethylene and the polyethyl tetraene think can pronouncing that right yes P see all I know about pla is it's used in 3D printing and it's not very radiation Toler cuz I wrote a research paper on it 3D printing is one of the main uses the other main use is basically packaging so if you want to have like a biodegradable

packaging specifically like the paper packaging uh you'd replace the plastic liner with PLA and boom your packaging is compostible industrially compostible though compostible under certain conditions yes and this is something that I think catches out a lot of packaging in the UK is that there is actually a standard for what is imposible but I don't know if everyone has followed that standard or the definition of the standard is compostable under certain conditions not

necessarily home compostable I would argue that uh most people don't Compass at home but then people might put it in their food waste bin which is what I wanted to do until I realized actually that doesn't belong unless it specifically says it on the packaging most of the places I've lived in the UK have had this sort of the garden waste bins where they'll also take kitchen scraps say so I'd have been inclined to put them in that as well but I don't know if I should have I say follow the

instructions on the packet oh which sometimes confuse me massively cuz I'm a pedant this is why I've done so much reading cuz it was like this is ambiguous what does curbside even mean h but you mentioned um p and p I'm not going to try and pronounce that one again P you did really well thank you these aren't biodegradable though are they but where do they come from if they're biologically sourced well technically the biobased will be biodegradable but under certain under only under certain

conditions so basically the biobased is you'd swap out the so in polyethylene you swap out the the ethylene with a bio ethylene and then you just basically go through the same reaction as with conventional ethylene to make biop PE uh for biop p it's again again similarly just use bioethylene and then have basically the same process okay so what you were going saying before right at the start about having alcohol-based sources is that right yeah it's ethylene or it may not be alcohol I I think so

like Eilene you normally get from natural gas cuz you can get it from from uh ethane if you get bio ethane then you can create bio ethylene pretty sure you can just you can create bio ethane from bio gas I may need to double check this okay so if I'm composting my stuff I'm going to keep going back to this because I do it at home and I'm one of the few people that do it turns out but gas comes off the compost and some of that could have some ethylene in it or some

methane and you can use that to make a biobased polymer uh okay so I was right about the alcohol so bioy is produced from bi bioethanol ah not ethane not ethane no but conventional ethylene is produced from natural gas it's either you get it from the ethane or it will be like another wet gas that's produced when you drill about oil and gas cuz yeah there were multiple different types of things in in natural gas yeah you'll get your methane ethane propane butane

and other gases but I think it's usually most of the time you would use you would use fossil Ean to produce Eilene okay but I I think I feel like I'm getting a little bit confused because we've been talking about um biodegradable things from biological sources Y and then kind of biological sources I'm not sure if natural gas counts biological source does it oh no it doesn't so that's for the conventional PE you when or your conventional P that are derived from

fossil ethylene which you would normally get from natural gas with the biobase you just use bioethylene which you get from bioethanol okay which you can make through various processes okay and they're still biodegradable the PE and the PT they should be in theory in theory are they in theory okay doesn't it just fall into smaller pieces all Plastics are biodegradable it just it takes it just takes a while but in the meantime we get microplastic isn't that the issue I'm not entirely sure how it

relates with biodegradability of different plastics it's like we've got big pieces physical pieces of plastic and in order to get it to biodegrade it has to be smaller pieces first but then in that interim we have problems with having lots of little bits of plastic which we call microplastics and I think the microplastics are problematic IC because they get into the water column and they float and disrupt little swimmy things that live there but they can also

get other places because we don't have a way of filtering them out yeah apparently all tap water in the UK contains macroplastics even the bottle water some of the bottle water does I guess there needs to be a definition of what is meant by biodegradable are you talking about breaking a big thing down into small things or are you talking about breaking it down from one chemical form into a different chemical form it's a good question cuz I assume that's what's meant by biodegradable that it's

degraded into molecules that don't persist in the natural world oh wait I just like to um clarify so I've just been reading uh biobase PE and P are not biodegradable but pla is yeah that's what I thought I'm pretty sure there was like this um quadrant system which was like bio source and biodegradable and then like some of them like are traditional hard plastics that did not sit in the biodegradable category cuz chemically it's the same as p and PE which don't naturally degrade

in tens of years it degrades in like hundreds thousand years so I feel like we've gotten to the bottom of this now they're basically sort of four classes of plastic depending on where they came from and depending on what can happen to them to I'm just going to say degrade of them because it doesn't really matter how you dispose of it necessarily yes cool so if we taking a while to get the Bott of that but I think it was worthwhile there was a little bit confusion there um but something else

that gets me about Plastics is we've mentioned it comes up in lots of different places is in clothing it's not something i' ever really thought about before but they make clothing stretch you talking about rubber before and I've heard that that does not degrade at all brilliantly in the environment and even once like say the cotton from some stretchy jeans has disappeared the stretchy stuff whatever it is still persists yeah so if you think about a lot of our clothes like stretchy jeans

love them cuz you know you don't have to worry about you eat a meal and then your don't fit but to make them stretchy it's not 100% cotton anymore it is going to be like 5% elastane and yes cotton exists naturally in the world and it does biodegrade but the elastane doesn't people have been coming up with alternatives to replace that there are a couple of I want to say a couple of different Fabrics but part of it is also branded fabric so like people will come

up with a thing like Spandex and Lyra which are brand names of I think the same chemical or same material I don't know if it's fair for me to say this but it does kind of make things a little bit more confusing because if you're talking about say Visos or rayon yeah do they mean wildly different things or are there some similarities I'm probably picking two completely ridiculous things to compare there so no I think they are very similar if not the same um they both come from cellulose

you know cellulose is nice tough material in nature which you can then turn into fibers and then that can become fabric now you got me thinking about bamboo but I think I'm getting distracted again now here's one thing that really confuses me yeah there are a lot of different materials that people claim their fabric to be made of but I think it all undergos similar processes it's like different biosources to produce the same end result like chemically they are the same is that

your understanding of it or have you not looked into it Jasmine all I can tell you is that Plastics made from cellulos are not biodegradable oh I would assume they are inherently but I guess chemically we've changed it from cellulose to something else but the majority the vast majority of plastic surv from silos they're categorized as non-biodegradable basically like pla is the only real biodegradable plastic that you have sh heart and you're too late you give Plastics or plants a bad name

well there are some others so like the starch based ones are biodegradable pla is the main one you also have some others that I cannot pronounce the full acronyms I must have confused Visos with another thing or maybe I knew but I just kind of thought at least it's from a renewable source instead of a fossil fuel source so silk right silk is biodegradable are we saying is that a polymer is that a plastic that's not a plastic but it's definitely B degradable

because it will get eaten by moths true yeah a little too too easy to degrade yeah oh what a Minefield I know I feel like I'm just finding out more things that I'd never even considered I just thought like cellulose is the best thing ever but maybe not it depends what you do with it right yeah if you chemically change cellulose into a fabric apparently it is no longer cellulose like and then the little creatures that exist in the house that keep eating my woolly things aren't going to eat it

which is helpful in a way yeah but then what do I do with it when I don't want the item anymore when I'm completely done with it and it's basically just rag how do I get rid of it burn it that's sound sustainable bio based there is a waste hierarchy for things and I think burning it is just one step above landfill you can get some use out of it yeah I guess if you burn it for war warm and not just for fun yeah hey bonfire night is never a waste uh pretty bad for air

pollution and um what's photochemical whatever smog no Strat ozone formation yes I couldn't remember which one it was who would have thought in an episode about bioplastics we'd end up talking about bon fire night hey you never know when you might need to just burn all your non-biodegradable clothes you are you on space I mean there isn't much space in London that's well we could well we could always you could always donate it if it's in a good quality but the issue is like in like

countries in Western countries because we produce and have so many clothes there's generally like an over supply of supply of the clothes that we donate and like recycling Fabrics it's still work in progress but it is possible to recycle plastic from a mechanical point of view but also a chemical point of view yeah yeah it is but um it's quite difficult to recycle is it visco Visos is that the that a biobased clothing fabric yeah it'll be quite difficult to

recycle is that because it's quite hard wearing so it would take quite an energy intensive process to break it down and turn it into something new or am I thinking about that in the wrong way uh it could be it could also just be that um how do you recycle a fabric like how do you get it back into the polymers that that that you need H so I guess I'm thinking about something like cotton where you just kind of shred it oh yeah cotton you could yeah that's easier yeah

or wool cuz I know how you sort of turn a fleece from a sheep into thread that's relatively straightforward I guess part of the problem is if you got like mixed fibers they have to be treated differently maybe yeah I thought there's a process called depolarization though it's called chemical recycling where you heat stuff up and it breaks down into the monomers so then you could reform the monomers yeah you do have that but for like a lot of fabrics it's usually just not 100% like Visos or

other biobased Fabrics so like how would you separate out the visco from other stuff so even if the clothing says 100% Visos are we are we not just able to to chemically recycle it you could I it depends on if you can find someone who's willing to do it yeah that is a huge challenge with the plastic recycling industry is that there isn't enough Logistics and recycling capacity and is there just not the capacity because I'm going to go back to my earlier point

it's like quite energy intensive to do it and there's just a more efficient process to make things from the original raw materials yeah yeah and I would also throw in that because there's so many different types of polymers just like a little bit of contamination between different polymers can really impact the quality of the end of the plastic that you end up with trying to not have contamination is also a really big issue with plastics even if you had like a

bioplastic source you'd still have the same problem with what to do with afterwards so like with the convential Plastics you have lots of different types of bioplastic so you can't just like if you did recycle them you have to make sure that you're recycling all the same kind rather than mixing and matching because like the poly are they're different they're different lengths so you can't really just like put like recycle a mixture of because it the end plastic that you end up with

after recycling will have very different properties to the um what like to like a p or a p for example okay so I guess going back to what we saying right at the top that bioplastics are about not relying on fossil fuel so much and reducing the impact of plastic waste only really solves half of the pered problem with plastics yeah so I guess we're sort of almost back to what we were saying in the original Plastics episode it's about sort of how long something lasts and get

getting the most amount of use out of it in that case so how long would I reasonably expect oo it's quite tricky cuz you said that bioplastics take up such a small percentage of the Plastics Market I was going to say how long how long would I reasonbly expect them to last but I guess maybe no one's really done that analysis you can do like a a bit of a accelerated stress test on them so I think people have a an idea so something I bought recently was a soap bar holder which is a starch based

bioplastic that is biodegradable yes so they're expecting that to Last 5 Years maybe in a shower that doesn't sound like a huge amount of time for something that i' I've bought for a use and it just sits there if you think about how long people usually keep like a soap dish for it's usually not that long I feel like people just leave it around like they'd move house and just like leave it behind yeah no I'm not that sort of person I take literally everything with me even if it wasn't

mine to begin with so my soap dish should last me forever until I die I suppose it could have other uses so like I don't know I've noticed in like house buying just like you know everyone moves house and then they go I don't like this person this previous person's style so I'm going to redo it doesn't matter if the carpet is like good quality they'll just take it out so you know there are some things that people use even though it would have a much use but they just change it

because of essentially fashion so we're saying fashion in people's behaviors of the enemy here not Plastics even regardless of how they're made yeah you can put that argument forward it's kind it's quite a valid one because there it's it's a really big issue when it comes to circularity is that so like things like a vacuum cleaner they're designed for really long lifespans so like 10 plus years but most people don't keep their vacuum cleaner for that long because a new model comes out that might

look nicer or have be more powerful and you then you get rid of your old vacuum cleaner after a few years people do that yeah I'm with an on this one I had mine for 14 years now this is a very weird conversation to have what how long have you had a vacuum cleaner but is it a really good vacuum cleaner though I've gone through a lot of vacuum cleaners in my time you're on the other end of the spectrum yeah that's getting into a very separate topic about adolesence yeah in what are you

reasonably expected to do to look after machinery and all that sort of thing I ask everyone to go to your vacuum cleaner and clean the filter I do that with the one that I'm using now because it's just easier to clean the filter in it oh yeah there we go that's a whole separate topic about how easy is something to use and how do you engineer a useful product rather than something you buy once think this is terrible and throw it out it's all other side of sustainability and how do you include

plastic in it as well or do you not is plastic really sustain aable I think it can be if it's used correctly but that's my very novice assumption no I agree yeah I agree it's just like we're just so accustomed to having plastic everywhere and we're used to like very specific use cases of things like the amount of like random things that do one job and one job only and then you throw it away it's seems ridiculous like why is a food shopping bag not also a b bag

why do we have different things for that back when single-use plastic bags were still given out for free and were still a thing my parents did use them as bin bags mine too but that wasn't normal I guess if you accumulate so many of them they just end up inherently being rubbish but I guess that's another question if it is a potentially high value material that could have multiple uses why is it being thrown out could you do something else with it could there have been some route with that

plastic bag was then sent somewhere to be turned into clothing and it was just an automatic think yeah potentially but I think it's also to do with that a lot of people don't view plastic as a high value material almost like from a philosophical point of view is like what kind of value are we talking like who assigned the value if we're talking economic value it's a plastic bag that people used to be given for free so they didn't pay anything for it so they don't

think it has any value but from like if you looked at it from a fossil fuel point of view that fossil fuel is never going to be made again In Our Lifetime well that is an interesting philosophical Point how much do you value something and how much can you afford to spend on something as well I I might be able to spend a lot on something but I don't necessarily want to I'd rather I put a lot of value in the things that I buy I guess regardless of where they come from if I had lots of

money I would definitely not spend it on just buying single- use plastic Cuttery that would just throw out and would you buy a dishwasher if I was living by myself I probably wouldn't need a dishwasher cuz I generate so little dirty dishes I feel like we've kind of strayed from talking about Plastics to talking about how we live basically I suppose that's what plastic is it is a story of how Humanity lives some he plastic is a lifestyle on that note we should end it right there and

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