What are the Different Uses of Polystyrene?

Polystyrene (Polystyrene, PS for short) refers to a polymer synthesized from a styrene monomer through a radical addition polymerization reaction. It is a colorless and transparent thermoplastic with a glass transition temperature above 100 ° C, so it is often used to make a variety of disposable containers that need to withstand the temperature of boiling water, and disposable foam lunch boxes. ^[1]

Polystyrene

Polystyrene (PS) refers to

In 1829, the Germans

Structural short form:

Polystyrene (PS) includes ordinary polystyrene, expanded polystyrene (EPS), high impact polystyrene (HIPS), and syndiotactic polystyrene (SPS). Ordinary polystyrene resin is non-toxic, odorless, colorless and transparent

ordinary

PS generally has a head-to-tail structure, and the main chain is saturated

Polystyrene is easy to process and has the advantages of transparency, cheapness, rigidity, insulation, and good printability. Can be widely used in the light industry market, daily decoration, lighting instructions and packaging. In the electrical aspect, it is a good insulation material and heat insulation material. It can be used to make various instrument housings, lampshades, optical chemical instrument parts, transparent films, capacitor dielectric layers, etc.

Can be used in powder and emulsion cosmetics. It has good compressibility and can improve the adhesion of powder. Gives skin luster and lubricity, and is an advanced filler that replaces talc and silica. ^[2]

Due to its low quality (especially foaming type) and low residual value, polystyrene is not easy to recycle. Generally, polystyrene cannot be recovered by the kerbside method. However, the reuse of expanded polystyrene has also been greatly improved in the industry, and many new methods for densification have appeared. This method of increasing its density usually increases the density by 15 slugs / ft3 (translator's note: 1 slugs / ft3 = 1.94055 g / cm3) and forms the center of a suitable regeneration operation on clean polystyrene.

The world s polystyrene (PS) production capacity

Polystyrene (foam board)

Rapidly growing and hitting record highs. By the end of the last century, the production capacity had exceeded 13 million tons per year, while the world's polystyrene consumption was only about 10 million tons per year, accounting for only about 77% of production capacity. Excluding the influence of various factors, the operating rate of global polystyrene plants has not exceeded 80%.

Since the beginning of 2000, the consumption of polystyrene in the world has slowed down, and the consumption has increased by only 1.4% compared with 1999. The growth rate is the lowest in recent years. Especially affected by the Asian financial crisis, the countries and regions with the largest output reductions are also concentrated in Asian regions. In 2003, the world's total production capacity of polystyrene was 14.26 million tons / year, and the output was 10.801 million tons / year. Of which North America's production capacity was 3.325 million tons / year, which accounted for about 22.8% of the world's total polystyrene production capacity. ; Output is 2.513 million tons / year, accounting for approximately 23.3% of the world's total output; production capacity in South America is 666,000 tons / year, accounting for approximately 4.8% of the world's total production capacity; output is 401,000 tons / year, accounting for approximately 3.7% of the world's total output; the production capacity of western Europe is 2.954 million tons / year, accounting for approximately 20.7% of the world's total production capacity; the output is 2.627 million tons / year, accounting for approximately 24.3% of the world's total output; The production capacity is 4.892 million tons / year, accounting for approximately 34.3% of the world's total production capacity; the output is 3.738 million tons / year, accounting for approximately 34.6% of the world's total output; the production capacity in Southeast Asia is 973,000 tons / year, accounting for approximately 6.8% of the world's total production capacity; output is 715,000 tons / year, accounting for 6.6% of the world's total output; production capacity in other regions is 1.525 million tons / year, accounting for 10.7% of the world's total production capacity; output is 80.7 10,000 tons / year, accounting for about 7.5% of the world's total output.

In 2003, the total consumption of polystyrene in the world was 10.889 million tons, of which 2.505 million tons / year was consumed in North America, accounting for about 23.0% of the world's total polystyrene consumption; South America's consumption was 445,000 tons. / Year, accounting for approximately 4.1% of the world's total consumption; consumption in Western Europe is 2.269 million tons / year, accounting for approximately 20.8% of total consumption; consumption in Northeast Asia is 4.092 million tons / year, accounting for approximately consumption The consumption in Southeast Asia is 498,000 tons / year, accounting for about 4.6% of the total consumption; the consumption in other regions is 1.08 million tons / year, accounting for about 9.9% of the total consumption. It can be seen that the production and sales of polystyrene in North and South America are basically balanced, and there is a slight surplus in Western Europe. Northeast Asia still needs to rely on imports to make up for the shortfall.

The world's polystyrene is mainly used in the production of packaging containers, daily necessities and electrical / electronic industries. The consumption structure of polystyrene varies across the world. About 9% in North America is used in the electrical / electronic industry, 57% is used in packaging containers, 34% is used in other aspects; about 15% in Western Europe is used in the electrical / electronic industry, 48% is used in packaging containers, and 37% is used in other aspects; About 49% in Northeast Asia is used in the electrical / electronic industry, 20% is used in packaging containers, 31% is used in other areas; about 63% in China is used in the electrical / electronic industry, 7% is used in packaging containers, and 30% is used in other areas .

Existing Problems

With the continuous innovation in the field of terminal applications, the main downstream products of polystyrene (PS) are gradually

Polystyrene sandwich panel series

Being replaced, the future may disappear. This has prompted some regional producers to completely withdraw from the business, and the PS industry is gradually being strangled.

A resin manufacturer in Taiwan, China believes: "The market lacks new areas that require heavy use of PS, so demand for PS will gradually decline, and this is not just caused by the global economic crisis."

In the production of new game consoles, mobile phones and MP3 players, polycarbonate (PC), acrylonitrile-butadiene-styrene (ABS), and polymethyl methacrylate have been used instead of PS. Applications of PS are limited to low-end products such as food packaging, toys, hangers, containers, and some consumer electronics. However, even in these areas, PS may gradually be replaced by cheaper raw materials such as polypropylene.

As an important market for PS, China's demand has shown a continuous decline since 2003. In 2003, demand exceeded 2.6 million tons, and in 2002 it fell to 2.3 million tons. Demand for the Japanese PS market has also fallen sharply, especially in electronics and industrial applications. Japan's major PS customers' production bases are gradually shifting overseas, which has made it impossible for Japan's domestic PS demand to resume.

Japan's original four PS manufacturers have a combined capacity of 1.1 million tons per year, which accounts for about 70% of their domestic market. Japan's polystyrene company, a joint venture between Mitsui Chemicals and Sumitomo Chemical, recently announced that it will withdraw from the PS business. By then, there will be only three companies in Japan that are engaged in the PS business. Mitsui Chemicals and Sumitomo Chemical stated that the company has decided to withdraw from the PS business because the business is in a very difficult situation and it is impossible to obtain stable income in the medium and long term. A producer said that Japanese PS demand is expected to fall by 6.5% to 7.0% to about 700,000 tons, and the withdrawal of Japanese polystyrene companies will make the supply and demand situation more balanced.

At the same time, Mitsubishi Chemical will also withdraw from its polystyrene Japan joint venture with Asahi Kasei Chemicals and Idemitsu Kosan. The company has a production capacity of about 445,000 tons / year, ranking first among the four Japanese manufacturers. Despite weak demand, Dainippon Ink and Chemicals (DIC) and Toyo Styrene, a joint venture between Denka and Daicel, will continue to produce PS.

In addition, the company that abandoned the PS business is the German chemical giant BASF. As early as July 2007, it announced the sale of various styrene units, including PS units. Idemitsu PS Malaysia also stopped production of its 30,000 tons / year general polystyrene in September 2008. The Dow Chemical Company has closed its 120,000-ton / year PS unit in eastern China indefinitely.