从China供应商批发进口90%-96% High Active Magnesium Oxide — FOB条款

Qingdao Topsen chemical supplies high active magnesium oxide with purity grades spanning 90.0% to 96.0% MgO, produced via the seawater method that yields controlled reactivity through precise calcination. The material is classified by iodine absorption value, with this offering falling in the high activity bracket of 120-180 mg I₂/g, distinguishing it from medium activity (50-80 mg I₂/g) and low activity (19-43 mg I₂/g) grades. Particle sizing is available at d₅₀ ≤ 150 μm for most grades, with one variant specified at d₅₀ ≤ 3.0 μm for applications demanding ultrafine dispersion. The supplier controls impurity content through raw material selection and thermal processing, targeting low heavy metal and chloride levels consistent with seawater-derived magnesia.

This product serves as an acid scavenger and vulcanisation activator in CR, FKM, CPE and CSM rubber compounding, where high surface reactivity accelerates crosslinking kinetics. In paper manufacture, it functions as an alkaline filler and buffering agent, improving brightness and dimensional stability. The paint and coatings sector employs it as a tinting extender and anti-settling agent, while specialised applications include steel ball polishing formulations, leather tanning auxiliaries, adhesive systems, and glass-reinforced plastic matrices where controlled magnesium oxide reactivity influences cure profiles. The calcination temperature window directly affects both surface area and reactivity, making batch consistency critical for end-use performance.

Buyers should confirm the specific purity grade (90.0%, 92.0%, 94.0% or 96.0% MgO) and corresponding particle size distribution that matches their formulation requirements. The supplier's harbour trust tier and zero recorded response rate suggest direct contact is essential to establish communication protocols, sample availability, and minimum order quantities. Typical packaging for industrial magnesia includes 25 kg multi-layer paper bags or bulk flexible intermediate bulk containers; moisture-proofing is necessary given magnesium oxide's hygroscopic nature and tendency to carbonate on air exposure. Incoterms and lead times require explicit confirmation with Qingdao Topsen chemical prior to order placement.

Qingdao Topsen chemical operates from Qingdao, Shandong Province, postal code 266000, in eastern China's coastal industrial corridor. The supplier holds a harbour trust tier classification on the platform, with no response rate or average response hours recorded in the available data. This absence of engagement metrics means buyers should initiate direct enquiry to assess responsiveness, technical support capability, and sample provision protocols. The company's specialisation in seawater-process magnesium oxide indicates access to brine resources and calcination infrastructure typical of Shandong's chemical manufacturing base.

The listing discloses production methodology (seawater process with temperature-controlled calcination) and a four-grade purity portfolio, but omits manufacturing capacity, quality management certifications, export experience, and specific client references. No information is provided on laboratory capabilities, third-party testing relationships, or environmental compliance documentation. Buyers should request evidence of consistent batch quality, specification sheets with actual test results for each grade, and clarification of whether the ≤ 3.0 μm grade is milled or precipitated to achieve its fine particle size. The supplier's address places it within Qingdao's port hinterland, potentially offering logistics advantages for bulk chemical export, though specific incoterms and shipping arrangements require direct negotiation.