PVC Foam Board Precipitation & Blooming Reasons and Solutions
PVC foam board precipitation & blooming reasons
and solutions
PVC foam board
after long-term Zhang and competition, the market commonly used foam board
basic positioning of the basic types of raw materials identified.
The reason is very
simple, with good compatibility with the PVC material in the case of appropriate
dosage will not precipitate, only with poor compatibility of PVC materials in
the amount exceeds the critical value will precipitate, precipitation is bound
to cause more Blooming phenomenon.
PVC foam board
often used additives lead salt / calcium zinc stabilizer, yellow and white
foam, foam regulator, stearic acid, 60,316 A, PE wax, calcium stearate, calcium
carbonate and other such materials
Foaming regulator
and PVC best compatibility, can promote the melting and plasticization of PVC,
the formation of network gel structure, brightening, and even reduce the
material precipitation.
Stearic acid,
calcium stearate, 60,316A is an internal lubricant, especially in the 316A
molecule with hydroxyl, etc., relatively good compatibility, 60 is an ester
lubricant, compatibility is better, stearic acid A little bit special, mainly
when the temperature is low, the main lubrication, the amount of more or high
temperature will be part of the role of changes in external lubrication even
precipitation, calcium stearate easy to form a layer of film on the surface of
the device, a long time easy scaling .
PE wax is a high
melting point external lubricant, poor compatibility with PVC, high
temperatures can form a film of metal and PVC molecules to prevent adhesion.
Stabilizer is PVC essential one of the most important additives, and now most
of the stabilizer is a complex stabilizer, in order to reduce costs, some
manufacturers in which to add paraffin, polyol and other small molecules, not
only with the PVC phase Poor performance, but also very easy to cause
precipitation.
In order to avoid
the occurrence of precipitation, we can take the following measures: First, a
variety of lubricants (low middle high melting point, internal and external
slip agent) with coordinated use, complement each other to make up for
deficiencies; Second, to ensure non-stick model Try to reduce the amount of
external lubricant, in the case of liquidity and plasticization to minimize the
amount of lubricant; third, the choice of stabilizer, try to choose high
quality and high price, do not understand can find our JuBang alibaba platform;
the fourth , Add a small amount of ultrafine silica precipitation will have
some improvement.
