Professional Graphite Electrodes & allied graphite product Supplier

Raw Material and Proportioning of Graphite Tube

(1) Raw materials
① phenolic resin with different alkaline catalysts made of phenolic resin graphite tube, its chemical stability is not very different, but in the toughness of sodium carbonate as a catalyst for the best resin, and the resin made of sodium hydroxide as a catalyst for the shrinkage and brittleness of the adhesive.
Phenolic resin viscosity requirements: When the use of funnel viscosity measurement, under the 20^€ 100ml resin through the phantom leg hole in the 3~7min flow. It is difficult to mix with fillers if it is sticky.
The moisture in the resin is controlled below 10% to reduce the pores left by evaporation of water during solidification. The content of free phenol in resin should not be too high, otherwise the curing speed is fast and unfavorable to construction.
② Curing Agent Phenolic resin contact acidic medium, at room temperature can be converted into a solid, this process is called curing, add acidic medium called curing agent. The phenolic resin cured by a lot of acidic medium, currently used most is benzene sulfonyl chloride and P-benzenesulfonyl chloride.
Benzene sulfonyl chloride at room temperature (> 15T) for liquid oil, and phenolic resin can be evenly mixed, acidity uniformity, curing speed suitable for construction requirements, adhesive quality is good, so the use of a wide range. However, because of the high toxicity of benzene sulfonyl chloride, volatile to human eyes and respiratory mucosa has a strong irritant, some people may have skin allergy after contact, so the construction should pay special attention to safety protection.
The methyl benzene sulfonyl chloride is solid at ambient temperature and can be used in fillers. Compared with benzene sulfonyl chloride, the toxicity is small, but the curing speed is slow, easy to absorb water damp, construction is difficult to control. However, if the construction method is mastered, the bonding quality can be ensured.
③ filler phenolic bonding agent used in a variety of fillers. The amount of filler is related to the viscosity of resin, construction method and density of filler. The ratio of general filler to resin is 100: ($number). When filling with graphite powder, the ratio is 100: (100 ~ 150).
(2) The formulation of graphite tube bonding agent is many, the variety and quantity of filler, curing agent and other additives can be changed, and the bonding agent for different properties and uses will be obtained.