Polypropylene glycol (4) butyl ether stands out among specialty chemicals because of its unique combination of physical and chemical properties. This substance, known by its molecular formula C13H28O5, carries a blend of polypropylene oxide units attached to a butyl group. With a structure that features a polypropylene glycol chain of four repeating units capped by a butyl ether, this liquid presents characteristics that set it apart from other glycols and ethers. Its transparent appearance and mild, faint odor come from its molecular structure and purity level. Usually, the product does not crystallize easily and stays flowable over a wide temperature range.
At room temperature, polypropylene glycol (4) butyl ether appears as a viscous, colorless to slightly yellowish liquid. It delivers a specific gravity of roughly 0.97 g/cm³, though that number varies with temperature and purity. The density plays a significant role in applications that require precise volumetric measurement, influencing everything from mixing to dosing. This chemical remains soluble in water and many organic solvents, making it adaptable for use in industrial solutions. Freezing point usually stays below -50°C, and boiling point hovers above 230°C, giving it a broad span of usability for both low- and high-temperature processes. Surface tension and viscosity reflect those of other medium-chain polyether glycols, and the product’s lack of crystallinity in regular storage means it does not settle out as flakes, powder, or pearls. In commercial trade, it typically comes in liquid form, shipped in drums or bulk containers to prevent moisture uptake.
Delving into its molecular build, the backbone consists of ethylene and propylene oxide repeating units attached to a terminal butyl group. This configuration allows the molecule to resist breaking down in the presence of mild acids, bases, or oxidizers, which matters during storage and long-term handling. The ether group at one end of the chain increases solubility in organic matrices, and the relatively short chain length (four units) limits its viscosity compared to longer-chained polyethers. This difference separates polypropylene glycol (4) butyl ether from other higher molecular weight glycols that often behave more like viscous oils or waxy solids.
Anyone who has worked in a chemical manufacturing plant or laboratory knows contamination risks and handling headaches pop up with every transport of specialty liquids. Polypropylene glycol (4) butyl ether’s low vapor pressure reduces the chance of inhalation, and the absence of significant dusting or fume hazards makes it safer than powdery chemicals or volatile solvents. Still, this chemical needs protection from moisture to preserve its purity. The liquid rarely forms crystals and never turns into a solid, powder, or pearl under typical ambient conditions. Dispensing from containers remains straightforward; viscosity at room temperature supports flow, but not so low that spills happen unchecked.
Products like polypropylene glycol (4) butyl ether must be coded right for regulatory compliance and international trade. The Harmonized System (HS Code) groups this material under polyether-alcohols and their derivatives, typically within the broader 3907 or 2909 heading, depending on local rules. Various nations check documentation closely to prevent shipping delays and classification disputes. Including the correct HS Code on shipping invoices and safety data sheets proves crucial; mistakes can bring regulatory fines or customs headaches.
Made from propylene oxide, butyl alcohol, and base catalysts, polypropylene glycol (4) butyl ether acts as an effective intermediate in inks, coatings, lubricant formulations, detergents, and personal care applications. It dissolves wide-ranging ingredients, suspends fine particles evenly, and promotes compatibility between otherwise immiscible compounds. Its role as a solvent comes from a blend of polarity and lubricity, while chain length and end-group chemistry determine how well it performs in different scenarios. Customers in plastics, elastomers, and surfactant industries value the material for its combination of flow, non-volatility, and process stability—each rooted in how production controls the reaction between base raw materials.
Polypropylene glycol (4) butyl ether does not fall under the category of highly hazardous or extremely flammable substances. Material safety data highlight its low acute toxicity and limited skin or eye irritation in standard use. Still, best lab and factory practice calls for gloves, goggles, and careful handling to prevent slip hazards and accidental contact. The product emits little vapor under normal storage but should stay capped and away from direct sunlight or heat. Spilled liquid wipes up without leaving crystals or residues, and spills do not pose the fire hazard of more volatile ethers. Disposal must follow local laws: even though it breaks down slowly in the environment and shows low potential for harm, proper waste management keeps waterways and soil free from chemical buildup. Emergency responders find the chemical presents no risk of explosion or rapid vaporization in fire events; that makes this material friendlier to work with than many other organic solvents or ether-based chemicals.
Having handled a variety of glycols and ethers on factory floors and in research labs, anyone with hands-on experience soon notices that polypropylene glycol (4) butyl ether’s combination of slick texture, slight odor, and resistance to crystallization makes it easy to blend and meter in production lines. It does not clump or separate out in storage tanks, so line workers and quality technicians spend less time troubleshooting batch inconsistencies. Technicians appreciate how a single material can help reduce inventory complexity, since another similar solvent or surfactant may require different pumps, hoses, or safety measures. Experience shows that checking drum seals and labels at every receipt protects against mix-ups, as similar-looking glycols sometimes cause confusion on busy docks. From quality assurance to shipping, a chemical's physical form—liquid, in this case—makes it much simpler to maintain an efficient, safe, and traceable workflow.
The biggest challenges in supply chains for specialty chemicals like polypropylene glycol (4) butyl ether center around purity, trace contamination, and documentation. Inconsistent purity levels from vendor to vendor mean each batch should be tested for water content and byproducts, often using gas chromatography or mass spectrometry. Batch traceability lets buyers track supply back to specific production runs, helping root out any quality issues before they affect final products. For companies managing a large material roster, working with reliable suppliers and confirming specifications against standard industry certificates reduces risk and supports process uptime. Training shipping staff and warehouse teams to spot off-color, odorous, or separated material further guards against process disruptions.
Plant safety teams and sustainability managers set high expectations for anything added to production lines or research benches. Polypropylene glycol (4) butyl ether earns a place in safer chemical lists because of its modest toxicity, low vapor emission, and chemical stability. Still, continuous process improvements can help further reduce waste and improve resource efficiency. Engineers and operators can specify closed-system transfer, implement spill containment, and use returnable drums to reduce plastic and steel consumption. Choosing polypropylene glycol (4) butyl ether instead of more hazardous alternatives helps companies cut down on workplace incidents and emergency response needs. In research and manufacturing, periodic environmental monitoring provides data to keep operations in line with best practices, tracking everything from wastewater discharge to air quality.
Deep knowledge of materials like polypropylene glycol (4) butyl ether, paired with hands-on familiarity, keeps chemical supply lines stable and processes efficient. By respecting its physical properties, regulatory requirements, and environmental footprint, managers and workers build safer, more resilient operations. As demand for specialty chemicals trends upward, companies that appreciate not just the specs, but also the lived realities of using, storing, and shipping these materials, gain the benefits of lower risk, better quality, and smoother production. That strategy works in the lab and on the warehouse floor alike.
Providing high-quality chemical products and logistics solutions for global trade partners.
