Exploring the Idea of ​​Circular Economy in Polystyrene Foam Tableware (6)

3.2.4 Questions About Bisphenol A

Is bisphenol A toxic? There have been controversies in the past.

Regarding bisphenol A as the substance of "environmental hormone", the "Q&A on Environmental Hormones Problem" published by the Daewoo Chemical Industry Association has described that the female hormone of bisphenol A affects one to ten thousandths of female hormones. Between 1 and 1, it shows little effect. Bisphenol A is a monomer of polycarbonate, epoxy resin and unsaturated polyester. Its molecular structure is shown in Fig. 1, while PS is polymerized by styrene monomer. The molecular structure is shown in Fig. 2.

From the comparison of the above two molecular structures, it can be known that they are not of the same type. PS does not contain the structure of bisphenol A, nor is it likely to contaminate bisphenol A impurities. In recent years, the American Plastics Industry Association has funded a study on the effects of bisphenol A at the Harvard University’s Hazard Analysis Center. According to a study published in 2004, “The evidence that bisphenol A causes an increase in male hormone secretion is seriously insufficient” . At present, plastic bottles and baby milk bottles used for drinking pure water and mineral water in daily life at home and abroad, and high-grade drinking cups, etc. are made of polycarbonate obtained by polymerizing bisphenol A and acetone monomers, and their health and safety. All have been recognized by the food hygiene organizations in various countries. Therefore, the bizarre argument that PSP cutlery contains bisphenol A substances will lead to abnormal reproductive function is simply nonsense.

3.2.5 PSP Tableware and CFCs

Before the 1990s, PS extrusion foam sheet production process mainly used CFCs as the traditional production process of foaming agent, and CFCs have been proved to have great damage to the atmospheric ozone layer, but from 1987 the United Nations atmospheric ozone layer protection The most important historical document is that since the Montreal Protocol was promulgated, CFCs have gradually been banned around the world, and instead, butane and pentane have been used as blowing agents. China's PSP tableware began in the mid-1980s and reached more than 50 manufacturing companies and more than 130 PS extrusion foam production lines in the mid-1980s. Most of them were Chinese-owned Taiwanese-owned enterprises, and most of their production lines had CFCs foamed. The agent has been eliminated and replaced with butane. A small part of the production lines and domestic production lines also received funding from the special multilateral fund established by the United Nations, and gradually eliminated the CFC foaming agent and switched to the butane blowing agent process. It is understood that the replacement work has basically been completed so that there is no problem with the PSP tableware production process destroying the atmospheric ozone layer. However, the defects of the butane and pentane blowing agents are mainly explosive, and they should also be noticed. However, irrelevant to the destruction of the ozone layer, the main solution is to strengthen management issues. At present, various countries are actively developing carbon dioxide as a blowing agent. The new process has been implemented in industrialized production lines.

3.2.6 PSP Tableware and Recycling

The view that PSP tableware cannot be recycled is also one of the main reasons for its ban. This is also a misunderstanding. As we all know, PSP is a thermoplastic and its waste is recyclable and it is indisputable fact. However, PSP dishes are light in weight, large in size, and relatively scattered in use, which indeed brings considerable difficulties to recycling. For this reason, since the end of the 1980s, eight states, Japan, South Korea, and Taiwan Province of China had banned and restricted the management of PSP's tableware. However, the implementation of the ban has not been able to solve environmental problems well since it is not suitable. The alternatives, in turn, caused inconvenience in use and made it more difficult to enforce the banned regulations. As a result, many bans were revoked, some were not implemented, and others were modified to meet certain recycling and recovery requirements.

3.2.6.1 United States

U.S. policy on the management of PSP products, Congress has not yet established formal regulations, but several states have begun legislation. Since 1988, 39 cities and towns in the United States have passed provisions to prohibit the use of SPS containers for food, but Many changes took place, but only a few cities and towns actually implemented them, and some of them were officially repealed. Most of them were mainly replaced by regulations that promoted recycling. However, the ban on the use of CFCs as blowing agents for PSP-packed products and containers has not been eliminated.

l In 1989, Iowa issued an ordinance decree that PSP material would be prohibited from being used for the production and sale of packaging and food containers if its waste recycling and reuse rate fails to reach the specified rate. The decree was lifted in 1995.

l In the United States of Maine, in 1997, the original decree on the ban on PSP food containers was changed to be used by government units for PSP food containers that must be recycled or otherwise disabled. Older persons who are provided to schools or need to eat in wheelchairs are not allowed to be disabled.

l In California and Oregon, the original ban on PSP food containers was amended in 1995 to achieve a 25% recovery rate.

l In North Carolina, the United States, in 1995, required the PSP food containers to contain at least 25% of the content of recycled materials in the original regulations, and changed the proportion of recycled materials.

• The “No Distribution, Sale, or Delivery of PSP Food Containers” promulgated by the State of South Carolina in the United States in 1992, but if the container contains recoverable recycled materials, the regulations have not yet been enforced.

In the early 1990s, eight pre-expanded polystyrene (EPS) and PSP manufacturers led by DOW Chemicals in the United States invested 160 million U.S. dollars to establish EPS (including PSP) packaging recycling companies and associations, focusing on promoting EPS products for industrial use. Recycling work. At present, there are more than 200 recycling points for industrial EPS products in the country, which constitute a national recycling system. Re-grinding and hot-melt methods are commonly used in recycling methods. The current EPS recovery rate has increased from 25% in 1995 to more than 30%. Due to the strengthening of recycling, in 2000, U.S. PSP tableware consumption reached 23.2 kt, an average annual increase of 8%, with an average recovery rate of 12%.

3.2.6.2 Germany

Germany is the country with the most stringent laws and regulations. In 1991, the “Regulations on Packaging Materials” was issued, which stipulated that the recycling rate of plastic packaging should reach 64%. And the responsibility is fully implemented by the manufacturer. In 1992, more than 400 companies including packaging materials, materials, consumer products manufacturers and traders formed DSD
(Dualsystem Deutshland) National Waste and Recycling System (Green Point), establishes separation and collection systems and collects “Green Point” fees for plastic packaging to subsidize recycling costs.

In Germany, PSP cutlery is not listed as a ban. Only the PSP used is not allowed to use CFCs as foaming agents. Since August 1991, Germany has completely banned PSP packaging materials containing CFCs. Although PSP has not been banned, it is difficult to recycle, high in cost, or limited in recycling, and is therefore selectively accepted by the German recycling system.