Common problems and solutions of PVC resin

（1） PVC resin impurities exceed the standard

When PVC resin is stored, the resin impurities exceed the standard due to the pollution of protective articles or bag wall

When the package of the product is damaged during transportation, impurities are brought into the operation of changing the package, and the customer

After unpacking, the goods are put aside for a long time, resulting in resin pollution and other additives contaminated during mixing

Impurities.

Solution: during PVC resin protection, ensure that the tarpaulin and bag wall are clean and tidy, and the PVC resin is in transit

During transportation, tarpaulin shall be covered, and the PVC resin packaging bag shall be replaced in time when it is damaged, and the belt shall be avoided during replacement

It is strictly forbidden to mix the materials for changing packages with normal resin. The packaging bag shall be cleaned before the use of PVC resin

Clean up to prevent the impurities accumulated on the bag wall from mixing in, and ensure that all additives are not polluted before mixing.

（2） Yellowing of PVC resin products

The thermal stability of PVC resin is low, the molecular weight distribution of PVC resin is uneven, and the processing heat stabilizer is helpful

Agent quality problem (batch replacement), too high barrel or head temperature, loss of temperature instrument control

The problem of decomposition and processing formula caused by over temperature.

Solution: when it is confirmed that the thermal stability of PVC resin is low, it can be required to replace it with one with higher thermal stability

Good PVC resin, change the stabilizer, reduce the processing temperature, reduce the amount of lubricant, adjust

Whole formula.

（3） PVC resin products have many crystal points (particles)

The "fish eye" of PVC resin is on the high side, the PVC resin contains plasticized tablets, the additives are polluted, and the mixing process

There are impurity mixing, formula problems and production rate effects.

Solution: detect the "fish eye" of PVC resin, replace V resin when it is high, and store PVC resin

Avoid pollution. During mixing, PVC resin is screened to prevent foreign matters from entering. The mixing equipment is cleaned and the machine head is cleaned

Filter screen cleaning, plasticizer quality confirmation, auxiliary material quality confirmation, adjustment of processing temperature and

Production rate.

（4） Production capacity (mainly for PVC resin products)

The fluidity of PVC resin is poor, and the PVC resin mixture sticks to the wall.

Solution: adjust the raw material model of PVC resin and select SG-5 PVC with good fluidity

Resin.

（5） The surface of wire and cable pellets is rough and pitted

The plasticization of PVC resin is poor, the lubrication outside the formula is insufficient, the particle size of filler is too large or the distribution is too wide,

The content of volatile matter in the material is large.

Solution: appropriately increase the mixing temperature, prolong the mixing time, and appropriately reduce the external pressure

Lubricant: increase the amount of external lubricant appropriately, replace the filler with smaller particle size, and check

Plasticizer to reduce the amount of low melting point lubricant.

（6） There are bulges and particles on the pipe wall

Polyvinyl chloride resin or other materials have high moisture and volatiles, and impurities are brought in and plasticized during mixing

Poor chemical performance.

Solution: avoid resin moisture absorption, appropriately increase the mixing temperature and prolong the mixing time

Check the source of impurities, reduce the amount of external lubricant and increase the amount of plasticizer.

（7） The surface of the plate is uneven, rough and dull

Poor plasticization, raw material moisture, high volatile matter and impurities mixed in the material.

Solution: reduce external lubricant, increase plasticization and appropriately increase mixing temperature

Extend the mixing time, check the source of impurities and remove impurities.

（8） Poor film transparency

The transparency of PVC resin is poor, the stabilizer has too great influence on the transparency, and the lubricant is selected

Improper.

Solution: replace the recommended PVC resin brand suitable for the current products and replace the transparency

Better stabilizer and replace appropriate lubricant.

（9） PVC resin caking

Polyvinyl chloride resin has high moisture and high temperature aging.

Solution: measure the resin moisture, control the resin moisture at about 0.15%, and avoid

Prevent PVC resin from contacting high-temperature equipment or pipes, and avoid rain or moisture during PVC resin transportation

（10） PVC resin is affected with moisture

Polyvinyl chloride resin has large moisture and is affected by moisture during transportation or storage.

Solution: control the moisture content of PVC resin and do a good job in the transportation and storage of products

For protection work, lay PVC resin in a cool and dry plant to dry.