PVC: ANGEL OR DEVIL?
PVC is increasingly characterised as an enemy material of the environment and harmful to health. Many materials bear the wording PVC FREE and with this label they are advertised or proposed as GREEN alternatives, i.e. environmentally friendly and healthy for humans.
But if PVC is harmful to health why are items such as catheters and blood transfusion bags, which are mainly composed of this polymer used within the medical field?
In a broad sense, plastic includes numerous materials in addition to PVC, including polypropylene (PP), polythene (PE), polyester (PET), polystyrene (PS).
We care about the environment and future of our planet and we all agree that we must work to reduce the use of plastics in general. But why do we consider PVC above all, to be the one we need to eradicate?
LET’S LEARN TO UNDERSTAND IT
Safe, resistant, stable and inert: PVC (or polyvinyl chloride) is the plastic that consumes fewer fossil raw materials, 57% obtained from common salt and only 43% from non-renewable resources [1].
It is certainly one of the most used plastics in the world, finding use in the most varied sectors: construction, automotive, packaging, furniture, supplies, clothing, food, sports and medical. It is used for the manufacture of both soft and rigid products: from pipes for the transport of drinking water to windows and from the coating of electrical cables to containers for food use, just to name a few examples of use.
Given the wide use, PVC is undoubtedly one of the most studied and well-known products from a technical-industrial, scientific and environmental point of view thanks to the numerous studies developed both nationally and internationally.
These have shown some particularities possessed by PVC such that, to date, replacing PVC with other materials is not yet so simple. But what are the properties that make PVC such a unique and reliable material?
• RESISTANT: PVC products are resistant to degradation. Often materials with long degradation times are associated with a greater negative impact on the environment. But is this really the case? Let’s take glass as an example: it has a degradation time of more than 4000 years and yet it is the sustainable material for excellence. The reason therefore lies in the methods of use and in its management once its function is exhausted.
PVC products, once their function is exhausted and, if managed as required by national regulations (ex: separate collection), will have an impact equivalent, if not less, to that of alternative materials. [2]
Resistance to degradation therefore leads to a reduction in purchase demand and a consequent reduction in the consumption of raw materials and natural resources.
• UNALTERABLE: PVC is a very stable molecule and hardly decomposes naturally until it becomes microplastic.
Microplastics are tiny pieces, usually smaller than 5 millimeters that are formed mainly as a result of the disintegration and deterioration of larger pieces of plastic [3]. Microplastic pollution is one of the emerging environmental threats around the world and the subject of intense research activities. From some recent studies [4], promoted by the Spanish Higher Council for Scientific Research and international universities, it is evident that the Mediterranean Sea is also one of the main theaters in which this phenomenon is highlighted. From the studies conducted it emerged that, although PVC is present among the types of microplastics found in the investigated waters, most of it is represented by polyethylene, polypropylene, polyester and polystyrene. In a more recent study [5], conducted in 2021 in the Aegean Sea, it is explicitly seen that PVC represents a decidedly minimal percentage of the microplastics detected in all three sites involved in the sampling, as shown by the following. figure:
• FIRE RESISTANT AND SELF-EXTINGUISHING: as far as fire performance is concerned, PVC is a hardly flammable and self-extinguishing material, characterised by a low heat of combustion compared to alternative materials. The smoke release from burning PVC is no more toxic than that of any other carbon-based material, such as wood. The hydrogen chloride (HCl) contained in the smoke is highly irritating and provides an immediate fire signal, acting as an escape alarm even for people caught in sleep. During a fire, PVC does not produce molten droplets or sparks which would contribute to its propagation but carbonises, thus creating a layer of protection against the spread of flame [6].
But, in the event of a fire in PVC products, are dioxins emitted?
Yes, the combustion of PVC can form dioxins which are however absorbed by the soot particles contained in the smoke gases. Acute or chronic health effects caused by the dioxins generated are therefore minimised. Many other carcinogenic substances are released during a fire, such as polycyclic aromatic hydrocarbons (PAHs) and fine particles, which present a much higher risk than dioxins. [7]
• RECYCLABLE: PVC has a clear advantage over other materials, being in fact a material that can be repeatedly recycled, even more than 8 times [8]. The motivation lies in its structure which during the recycling process does not reduce its size while maintaining the performance characteristics. It has been calculated that with recycled PVC it is possible to obtain CO2 savings of up to 92% and the amount of energy required for regeneration is reduced from 45% to 90% compared to the production of “new” PVC [9].
• CONVERTIBLE: Polylaminate PVC can also be included in the waste-to-energy process, replacing fossil fuels with consequent generation of electricity.
In this regard, it would be appropriate to dispel some clichés that are too often cited when it comes to the incineration of plastics.
The term incineration is often associated with an uncontrolled emission of dioxins and unknown and harmful substances into the atmosphere. This could have been true in the 1980s when these combustion products were detected in the Amsterdam incinerator, rightly causing the blockade of incinerators across Europe.
Today, the European and National legislation concerning atmospheric emissions sets extremely strict limits for each substance and modern plants are managed in such a way as to remain well below these values. By way of example, it has been calculated that, in terms of global emissions, four waste-to-energy plants, operating at full capacity and built in compliance with recent regulations, would produce carbon monoxide emissions (expressed in kg / hour) equal to those produced by 9 mopeds with the same period of operation [10].
• PRINTABLE: PVC is perfectly printable with most digital, screen and rotogravure printing technologies and does not need to apply surface treatments that promote ink anchoring.
APA, PVC and THE ENVIRONMENT
To date, PVC has proved to be the most versatile material capable of satisfying and combining all the characteristics that self-adhesive films must respond to.
In order to guarantee a safe product to the consumer, APA undertakes to certify the compliance of its products with all the requirements established by the European REACH and RoHS regulations.
In particular, all the chemical compounds used, the plasticisers, the pigments and the additives comply with the European regulations on chemical substances and APA ensures the total absence of heavy metals such as cadmium, lead and chromium. Many APA products, following tests conducted by accredited laboratories, are also certified in terms of fire resistance.
APA uses and is constantly looking for the best technical solutions to minimise the impact of its production process on the environment, in particular by focusing on CO2 emissions.
Furthermore, in collaboration with PVC forum Italia and VinylPlus, APA is committed to managing PVC responsibly, studying increasingly cutting-edge solutions and respecting the environment around us.
Since 2021, APA has started a partnership with an important society that deals with the recovery and complete recycle of waste PVC films. As part of the disposal of non-recyclable waste, these are entrusted to selected suppliers who use the latest generation of waste-to-energy plants, allowing the production of energy with low emissions and replacing classic fossil fuels, at the same time favoring the reduction of landfill use for the disposal of waste.
Bibliography
[1] PVC Forum, Regia, PVC, an efficient and sustainable material. [Movie].
[2] C. Ciotti, “Waste-to-energy of PVC: it’s not a problem,” La Chimica & l’Industria, May 2012.
[3] European Parliament, «Microplastics: origins, effects and solutions, » 22 11 2018. [Online]. Available: https: /www.europarl.europa.eu/news/it/headlines/society/20181116STO19217/microplastics-origini-effetti-and-soluzioni.
[4] V. S. S. C. Shivika Sharma, «Microplastics in the Mediterranean Sea: Sources, Pollution Intensity, Sea Health, and RegulatoryPolicies,» Frontiers in Marine Science, May 2021.
[5] C. Z. F. G. C. G. Argyro Adamopoulou, «Distribution Patterns of Floating Microplastics in Open and Coastal Waters of the Eastern Mediterranean Sea (Ionian, Aegean, and Levantine Seas),» Frontiers in Marine Science, September 2021.
[6] PVC Forum Italia, «The fire behavior of building materials, focus on PVC, » [Online].
[7] PVC Information Center, PVC: Getting to Know It.
[8] C. Ciotti, “VINYLPLUS AND THE RECYCLING OF PVC: objectives, results, problems, innovation,” La Chimica e l’Industria, 2014.
[9] PVC Forum Italia, «PVC: History, production, transformation, market and current and future sustainability».
[10] Federchimica / PlasticsEurope Italia, «Plastics and energy recovery, » Chemistry & Plastics, October 2007.