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This. I don't understand all this plastic hysteria. Plastic is the ultimate material for food preservation. Most people dispose of plastic in the legal way that

This. I don't understand all this plastic hysteria. Plastic is the ultimate material for food preservation. Most people dispose of plastic in the legal way that is provided to them, so how does it end up polluting the environment? If it's the Big Bad Corporate Guy who in the end dumps all that plastic in the oceans, maybe the wrong problem is being solved here?

eesmith 5y ago
While it's legal to throw plastic in the trash, rather than "recycle"[1], trash which ends up in the landfill is more likely to get blown away or get carried away by water. How many is "Most"? If 5% don't, that's still a lot of trash. Plastic doesn't really help preserve bananas and oranges, which are two of the fruits on the immediate list. Plastic shouldn't be used as a psychological comfort simply because people "do not want their fruit to be touched by other customers". We could totalally go after "Big Bad Corporate Guy". But the issue there is that keeping the plastics completely out of the environment is expensive. Rather than increase waste fees (making the consumer and/or city pay in perpetuity for the plastic trash), shift the cost to the producer by requiring something other than plastic, and let the market figure out cost-effective solutions. [1] (in quotes, because that plastic might go to a special plastic incinerator instead of being recycled)
- neverminder 5y ago
  > But the issue there is that keeping the plastics completely out of the environment is expensive. I find it hard to believe that somehow we are able to manufacture plastic out of raw materials very cheaply, but converting it back to raw materials is so expensive. Maybe simply more research needs to be done in the area?
  - eesmith 5y ago
    There's a lot of research in the area, because there's a LOT of money to be made if the problem is solved. Here's one paper from 12 years ago, titled "Plastics recycling: challenges and opportunities" - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2873020/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2873020/ I'll provide a few quotes, with key parts in italics > It is possible in theory to closed-loop recycle most thermoplastics, however, plastic packaging frequently uses a wide variety of different polymers and other materials such as metals, paper, pigments, inks and adhesives that increases the difficulty. Closed-loop recycling is most practical when the polymer constituent can be (i) effectively separated from sources of contamination and (ii) stabilized against degradation during reprocessing and subsequent use. Ideally, the plastic waste stream for reprocessing would also consist of a narrow range of polymer grades to reduce the difficulty of replacing virgin resin directly. .... > Chemical or feedstock recycling has the advantage of recovering the petrochemical constituents of the polymer, which can then be used to re-manufacture plastic or to make other synthetic chemicals. However, while technically feasible it has generally been found to be uneconomic without significant subsidies because of the low price of petrochemical feedstock compared with the plant and process costs incurred to produce monomers from waste plastic (Patel et al. 2000). This is not surprising as it is effectively reversing the energy-intensive polymerization previously carried out during plastic manufacture. ... > Thermosetting polymers such as unsaturated polyester or epoxy resin cannot be mechanically recycled, except to be potentially re-used as filler materials once they have been size-reduced or pulverized to fine particles or powders (Rebeiz & Craft 1995). This is because thermoset plastics are permanently cross-linked in manufacture, and therefore cannot be re-melted and re-formed. ... > A major challenge for producing recycled resins from plastic wastes is that most different plastic types are not compatible with each other because of inherent immiscibility at the molecular level, and differences in processing requirements at a macro-scale. For example, a small amount of PVC contaminant present in a PET recycle stream will degrade the recycled PET resin owing to evolution of hydrochloric acid gas from the PVC at a higher temperature required to melt and reprocess PET. Conversely, PET in a PVC recycle stream will form solid lumps of undispersed crystalline PET, which significantly reduces the value of the recycled material.
chefkoch 5y ago
But does it? Lots of plastic is exported for "Recycling" ends up polluting 3rd world countries or in local landfills.

eesmith 5y ago

While it's legal to throw plastic in the trash, rather than "recycle"[1], trash which ends up in the landfill is more likely to get blown away or get carried away by water. How many is "Most"? If 5% don't, that's still a lot of trash. Plastic doesn't really help preserve bananas and oranges, which are two of the fruits on the immediate list. Plastic shouldn't be used as a psychological comfort simply because people "do not want their fruit to be touched by other customers". We could totalally go after "Big Bad Corporate Guy". But the issue there is that keeping the plastics completely out of the environment is expensive. Rather than increase waste fees (making the consumer and/or city pay in perpetuity for the plastic trash), shift the cost to the producer by requiring something other than plastic, and let the market figure out cost-effective solutions. [1] (in quotes, because that plastic might go to a special plastic incinerator instead of being recycled)

neverminder 5y ago
> But the issue there is that keeping the plastics completely out of the environment is expensive. I find it hard to believe that somehow we are able to manufacture plastic out of raw materials very cheaply, but converting it back to raw materials is so expensive. Maybe simply more research needs to be done in the area?
- eesmith 5y ago
  There's a lot of research in the area, because there's a LOT of money to be made if the problem is solved. Here's one paper from 12 years ago, titled "Plastics recycling: challenges and opportunities" - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2873020/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2873020/ I'll provide a few quotes, with key parts in italics > It is possible in theory to closed-loop recycle most thermoplastics, however, plastic packaging frequently uses a wide variety of different polymers and other materials such as metals, paper, pigments, inks and adhesives that increases the difficulty. Closed-loop recycling is most practical when the polymer constituent can be (i) effectively separated from sources of contamination and (ii) stabilized against degradation during reprocessing and subsequent use. Ideally, the plastic waste stream for reprocessing would also consist of a narrow range of polymer grades to reduce the difficulty of replacing virgin resin directly. .... > Chemical or feedstock recycling has the advantage of recovering the petrochemical constituents of the polymer, which can then be used to re-manufacture plastic or to make other synthetic chemicals. However, while technically feasible it has generally been found to be uneconomic without significant subsidies because of the low price of petrochemical feedstock compared with the plant and process costs incurred to produce monomers from waste plastic (Patel et al. 2000). This is not surprising as it is effectively reversing the energy-intensive polymerization previously carried out during plastic manufacture. ... > Thermosetting polymers such as unsaturated polyester or epoxy resin cannot be mechanically recycled, except to be potentially re-used as filler materials once they have been size-reduced or pulverized to fine particles or powders (Rebeiz & Craft 1995). This is because thermoset plastics are permanently cross-linked in manufacture, and therefore cannot be re-melted and re-formed. ... > A major challenge for producing recycled resins from plastic wastes is that most different plastic types are not compatible with each other because of inherent immiscibility at the molecular level, and differences in processing requirements at a macro-scale. For example, a small amount of PVC contaminant present in a PET recycle stream will degrade the recycled PET resin owing to evolution of hydrochloric acid gas from the PVC at a higher temperature required to melt and reprocess PET. Conversely, PET in a PVC recycle stream will form solid lumps of undispersed crystalline PET, which significantly reduces the value of the recycled material.

chefkoch 5y ago

But does it? Lots of plastic is exported for "Recycling" ends up polluting 3rd world countries or in local landfills.