Styrene (CAS: 100-42-5) and polystyrene (CAS 9003-53-6) are two different chemical substances. Styrene is the monomer used to synthesize polystyrene; it is a colorless liquid at room temperature, while polystyrene is a solid plastic polymerized from styrene. They differ significantly in chemical structure, physical properties, chemical stability, and applications.
Chemical Structure and Composition
Styrene has the chemical formula C₈H₈, containing a benzene ring and carbon-carbon double bonds, and belongs to the unsaturated hydrocarbon class. Polystyrene has the chemical formula (C₈H₈)ₙ, and is a polymer formed by the free radical addition polymerization of styrene monomers. The double bonds in its molecule have been broken and formed a long chain structure, thus no longer possessing the double bond characteristic.
Physical Properties
- State and Appearance: Styrene is a colorless, transparent liquid at room temperature with a pungent odor; polystyrene is a colorless, transparent solid, rigid and brittle.
- Thermal Properties: Styrene has a boiling point of approximately 145℃ and is easily volatile; polystyrene has no fixed melting point and softens easily when heated (softening temperature approximately 80–100℃), with a glass transition temperature above 100℃.
- Density and Solubility: Styrene has a density close to water, is sparingly soluble in water but soluble in ethanol and ether; polystyrene has a slightly higher density than water (1.04–1.13 g/cm³), good water resistance, but is easily soluble in organic solvents such as chloroform and toluene.
Chemical Properties
- Reactivity: Due to the presence of double bonds, styrene is chemically reactive and prone to oxidation and polymerization reactions (e.g., it will gradually polymerize and change color when exposed to air), requiring the addition of polymerization inhibitors during storage. Polystyrene molecules do not have double bonds, resulting in higher chemical stability, making it less susceptible to oxidation and exhibiting strong resistance to acid and alkali corrosion.
- Mechanical Properties: Polystyrene possesses certain mechanical strength and rigidity, making it suitable for use as a structural material; styrene, being a liquid, has no mechanical strength.
Applications
Styrene (CAS: 100-42-5) is commonly used as a chemical raw material, while polystyrene has wide applications in industry.
Polystyrene (CAS 9003-53-6) is an impact-resistant, insulating, and transparent material that can be used to make films, insulation materials, boxes, furniture, toys, etc.
Why Choose Gneebio as Your Supplier?
As a Styrene manufacturer, Gneebio focuses on product consistency, industrial applicability, and bulk supply reliability. The company operates under strict quality management systems to ensure that cyclohexanone meets the requirements of large-scale and continuous production environments.
Key manufacturing and supply strengths include:
- Controlled purity grades suitable for industrial and synthetic applications
- Stable batch-to-batch quality for long-term procurement
- Bulk supply capability to support contract and spot orders
- Export-ready packaging and documentation (COA, SDS, etc.)
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