From high-index optical lenses to low-temperature epoxy curing — four thiol products to solve your formulation challenges
Polymercaptan, mercaptan, and polythiol compounds play an irreplaceable role in optical materials, UV curing, low-temperature curing, metal adhesion, and more, thanks to their unique reactivity — they readily undergo thiol-ene and thiol-epoxy click reactions with isocyanates, epoxies, and unsaturated double bonds. Sinocure Chemical Group offers four high-performance thiol products covering a wide range of applications, from high-index lenses to UV anti‑oxygen‑inhibition and low‑temperature epoxy curing.
Chemical name: Bis(2-mercaptoethyl) sulfide
CAS No.: 3570-55-6
BMES is a difunctional mercaptan containing two thiol groups, developed for high‑index optical materials.
Key advantages:
High refractive index: Up to 1.59–1.60, ideal for 1.60+ index resin lenses.
Very low color: APHA ≤ 15, excellent light transmittance, no yellowing.
Low moisture content: ≤ 1000 ppm, minimizing bubble and haze formation.
Low viscosity: Liquid form, easy to process and blend.
Applications:
High‑index optical lenses: Core monomer for 1.60+ index lenses — thinner, lighter, and clearer.
Specialty anti‑corrosion coatings: Thiol groups form strong bonds with metal ions, creating a protective barrier on metal surfaces against corrosive environments.
Organic synthesis intermediate: Key building block for sulfur‑containing pharmaceuticals, agrochemicals, and high‑performance polymers; also used to synthesize luminescent polynuclear gold(I) phosphine complexes.
Coordination chemistry & catalysis: Acts as a bidentate sulfur ligand to form stable metal complexes with nickel, iron, etc., for catalytic hydrogenation and other reactions.
Chemical name: 2,3-bis((2-mercaptoethyl)thio)-1-propanethiol;1,2-Bis[(2-mercaptoethyl)thio]-3-mercaptopropane
CAS No: 131538-00-6
BMPT is a multifunctional mercaptan specifically developed for 1.60 and 1.67 high‑index resin lenses. It reacts with isocyanates or epoxies via thiol‑ene or thiol‑epoxy reactions to form highly crosslinked optical polymers.
Product highlights:
High refractive index (1.63–1.64), perfectly matched for 1.60/1.67 lenses
High Abbe number, sharp images with no chromatic aberration
High impact resistance, lenses resist breakage
Good dyeability, enabling various tinted lens colors
Compatible with precision progressive lens designs
Main applications:
1.67 high‑index ophthalmic lenses
High‑index optical lens elements
Precision optical lens UV adhesives (for lens assembly and bonding)
Optical coatings
Chemical name: Pentaerythritol Tetra(3-Mercaptopropionate)
CAS No.: 7575-23-7
PETMP is a tetrafunctional polythiol with 25–27% mercapto content, refractive index ≥ 1.529, extremely low color (Hazen ≤ 15), and much lower odor than traditional mercaptans.
Key features:
Fast cure & oxygen inhibition resistance: Acts as a co‑initiator in UV radical systems to overcome surface oxygen inhibition.
Low shrinkage: Thiol‑ene/epoxy click polymerization exhibits much lower volume shrinkage than conventional acrylates.
Excellent adhesion: Thiol groups naturally bond to metals, glass, and other surfaces.
Low‑temperature curing: Can quickly cure epoxy resins at room temperature or even low temperatures.
Applications:
High‑index optical resin monomer synthesis
Modifier and crosslinker for UV coatings, inks, and adhesives
Acidic ion exchange catalysts
Low‑temperature curing agents (epoxy/isocyanate systems)
PM839 is a liquid polymercaptan curing agent that serves as a direct replacement for CAPCURE® 3-800 Curing Agent, GABEPRO GPM-800, and Toray POLYTHIOL QE-340M. It offers a mercapto equivalent ≥ 3.0 meq/g, moderate viscosity, and low total chlorine content (≤ 800 ppm).
Key features:
Fast low‑temperature curing: Achieves high lap shear strength within 30 minutes even at −5°C when combined with epoxy resin and DMP‑30 accelerator.
Excellent thin‑film cure: Particularly suitable for thin bond lines where conventional amine hardeners cure slowly.
Light color, low chlorine: Hazen ≤ 20, total chlorine ≤ 800 ppm, suitable for electronic‑grade applications.
Adjustable pot life: Gel time can be tuned by accelerator dosage.
Typical applications:
Low‑temperature rapid curing of epoxy resins (especially for winter construction)
PV silicon wafer processing (temporary bonding/debonding)
Jewelry and craft bonding
Electronic adhesives
Anti‑corrosion coatings
Product | Functionality | Key Features | Main Applications |
2 | High RI (1.59–1.60), very low color, low viscosity | High index lenses, anti corrosion coatings, organic synthesis intermediate | |
3 | High RI (1.63–1.64), high impact resistance, high Abbe number | 1.60/1.67 high index lenses, precision lens UV adhesives, optical coatings | |
4 | High purity, low odor, oxygen inhibition resistance, low shrinkage | UV coatings/inks/adhesives crosslinker, high index resins, low temp curing | |
3 | Fast low temp curing, excellent thin film cure, low chlorine; direct replacement for CAPCURE® 3-800 / GPM-800 / QE-340M | Epoxy low temp curing agent, electronic adhesives, PV wafer processing, anti corrosion coatings |
Sinocure Chemical Group offers a complete polythiol product line from optical‑grade monomers to industrial‑grade curing agents. Whether you need to increase lens refractive index or solve winter epoxy curing challenges, we have proven solutions.
Request samples or technical support: Contact our sales team for TDS, SDS, and formulation optimization assistance.
Data based on typical test results. Actual performance should be verified through laboratory trials.
