Testing item

Testing requirement

appearance

white or almost white powder, odorless, tasteless

identification

meet the specification

degree of polymerization

≤350

fineness, %

60 mesh residue on sieve≤0.1

400 mesh residue on sieve≤1

grain size D50, μm

PH

5.0~7.5

chloride, %

≤0.03

water solubles, %

≤0.25

specific conductance, us/cm

≤75

residue on ignition, %

≤0.10

loss on drying, %

≤7.0

ether dissolved substance, %

≤0.05

heavy metal, ppm

≤10

microbial limit

bacteria,cfu/g

≤1000 

mould,cfu/g

≤100 

pathogenic bacterium

not detectable