1. What is ZTS? Chemical identity & structure

ZTS is the zinc salt of p-toluenesulfinic acid (the 4-methyl isomer of benzenesulfinic acid). Structurally it can be considered as Zn²⁺ coordinated to two p-toluenesulfinate anions (one sulfinic-acid derived anion per ligand). The result is a neutral salt (often isolated as an anhydrous white powder or hydrated form) used industrially and in research. Representative structural depictions and vendor images show the two aryl-sulfinylate groups bound to a zinc center.

2. Key physical & chemical properties

• Appearance: white to off-white powder.

• Molecular formula & weight: C₁₄H₁₄O₄S₂Zn; ~375.78 g·mol⁻¹.

• Melting / decomposition: reported ~251 °C (decomp).

• Boiling / thermal behaviour: high decomposition point; listed boiling point ~340 °C at 760 mmHg in some vendor sheets (likely decomposition).

• Density / physical constants: vendor sources list density ~1.36 g·cm⁻³ and calculated logP values in the literature/online calculators vary (indicating a fairly hydrophobic organic component).

• Solubility: many commercial datasheets and catalog entries note low solubility in water (sparingly soluble/insoluble) and greater solubility in strong acids (e.g., nitric acid) or organic solvents depending on form and hydration. This follows from the aromatic (tolyl) groups and the metal-salt lattice.

3. How is ZTS made?

Commercially, ZTS is prepared by neutralization/metalation of p-toluenesulfinic acid with zinc salts (e.g., zinc oxide, zinc carbonate or soluble zinc salts) or by salt metathesis from sodium/potassium p-toluenesulfinate and a zinc(II) source. The typical stoichiometry is two equivalents of the sulfinic acid (or sulfinicate anion) per Zn²⁺. Vendor pages and product descriptions emphasize simple salt formation chemistry rather than elaborate multi-step synthesis.

4. Functional behaviour & mechanism in applications

ZTS is used industrially as a specialty zinc salt with activity derived from the sulfinic (sulfinate) ligand and the Lewis acidity of Zn²⁺.

• Foaming / blowing agent aid: used as an active agent or co-agent in foaming/blowing systems (e.g., in certain polymer foam formulations) where it can influence gas evolution or stabilization.

• Stabilizer / activator in polymer processing: reported as a stabilizer, lubricant or activator in synthetic rubber, PVC and other polymer systems; likely acts by coordinating to polymer or additive moieties and altering decomposition/curing/foaming chemistry.

• Catalytic / reagent roles (laboratory & R&D): as a zinc salt of a soft sulfinic ligand it may be employed in specialty syntheses or as a reagent/precursor in materials chemistry (less common than more standard zinc salts but used where the sulfininate ligand confers desired solubility or reactivity).

Mechanistically, the sulfinate group is nucleophilic at sulfur/oxygen and the zinc center is a Lewis acid; functions such as activation of labile bonds, coordination to polymeric chains, or promoting decomposition/transfer reactions are plausible explanations for the observed utility in formulations.

5. Applications

• Polymers & foams: additive/activator in PVC, PE and synthetic rubber formulations; used in some blowing/foaming systems.

• Additives & lubricants: described as a stabilizer or lubricant and sometimes used in specialty metal-organic additive blends.

• Chemical intermediates / R&D reagents: cataloged by chemical suppliers for research use in synthesis and materials labs.

6. Handling, storage & safety

• Hazard classification: According to available SDS summaries, ZTS is classified as very toxic to aquatic life (H400).

• First aid & exposure: avoid inhalation/contact; in case of exposure, remove contaminated clothing, flush skin/eyes with water and seek medical advice.

• Storage: store in a cool, dry, well-ventilated area, in tightly closed containers, away from strong oxidizers and incompatible materials. Many vendors advise storing under conditions to avoid moisture uptake (if anhydrous) or to control hydration state.

• Environmental precautions: avoid release to watercourses; collect spills and dispose according to local regulations. The H400 aquatic toxicity warning appears in supplier SDS docs.

7. Analytical & quality control considerations

Common characterization methods for a compound such as ZTS include:

• Elemental analysis (C/H/S/Zn): to confirm stoichiometry.

• IR spectroscopy: characteristic S–O stretching bands for sulfinate groups; aromatic bands for tolyl rings.

• NMR (¹H, ¹³C): aromatic and methyl signals from p-tolyl groups — note that paramagnetism is not expected, so NMR of the organic ligands is usually straightforward if the salt dissolves in suitable solvents (DMSO-d₆, DMF-d₇, etc.) or after acidification to recover the ligand.

• Melting point / TGA / DSC: thermal behaviour and decomposition temperature.

• ICP or AAS: Zn content.

• XRD / powder diffraction: to characterize crystalline form (anhydrous vs hydrated).

8. Practical recommendations for practitioners

Get the SDS & COA before first use. Verify purity, water content and the stated hazards. 

• Small-scale testing: confirm solubility and performance in your formulation (e.g., polymer blend, foam formulation) — don’t assume vendor claims transfer unchanged to your system.

• Waste handling: collect and dispose of residues as hazardous waste if local rules require it; prevent wastewater discharge.

• Analytical checks: use elemental analysis / ICP for zinc content and IR/NMR for organic ligand verification where necessary.