For procurement managers and R&D scientists tasked with sourcing chemical raw materials, understanding product specifications is crucial for making informed purchasing decisions. Dipropylene Glycol Diacrylate (DPGDA), a vital UV monomer, is no exception. Knowing the key specifications of DPGDA will help you ensure you buy a product that meets your formulation and application needs. Let's explore the critical parameters that define DPGDA quality.

When you buy DPGDA, the first specification you'll likely encounter is its Appearance. High-quality DPGDA is typically described as a transparent or colorless liquid. Any cloudiness or significant coloration could indicate impurities or degradation.

Viscosity is another critical factor. DPGDA is known for its low viscosity, which is advantageous for ease of handling, mixing, and application in formulations. Typical specifications might list a viscosity range, for example, between 7-13 cps at 25ºC. This low viscosity allows it to act as an effective reactive diluent, reducing the overall viscosity of UV-curable systems without the need for volatile organic compounds (VOCs).

Purity is paramount. While DPGDA is generally supplied with high purity, manufacturers often specify a purity level, sometimes indicated by GC (Gas Chromatography). For instance, a specification might be '>80%' or '≥95%'. The presence of isomers or related compounds can affect curing speed and final properties. Understanding the purity you are buying is essential for consistent performance.

The Acid Value is a measure of the residual acidity in the monomer. For DPGDA, a low acid value, typically ≤0.5 mg KOH/g, is desirable. High acid values can negatively impact the stability of UV formulations and may cause issues with certain catalysts or substrates.

Another important parameter is the Polymerization Inhibitor content, usually expressed in ppm. Inhibitors are added to prevent premature polymerization during storage and transport. Common inhibitors like MEHQ (Monomethyl Ether of Hydroquinone) are added in controlled amounts, typically ≤300 ppm. The inhibitor level is crucial for balancing shelf-life and curing reactivity. If you are buying DPGDA for a very fast-curing application, you might need to consider the impact of the inhibitor.

The Refractive Index (around 1.449) and Surface Tension (around 32.4 dynes/cm at 20ºC) are also technical properties that can be useful for quality control and characterization. The Glass Transition Temperature (Tg), often around 96ºC, provides insight into the thermal properties of the polymer formed from DPGDA.

When you decide to buy DPGDA, requesting a detailed Technical Data Sheet (TDS) from your chosen supplier is highly recommended. This document will outline all the relevant specifications, allowing you to compare products and make an informed decision. For reliable sourcing, always partner with experienced manufacturers who prioritize quality and transparency in their product offerings.