Polyvinyl Alcohol PVOH®725
ANHUI LIWEI CHEMICAL CO.,LIMITED
[Introduction]
PVOH®725 is a fully hydrolyzed medium molecular weight polyvinyl alcohol (PVOH). Using our exclusive batch process which has advantages over other manufacturing methods,allows more efficient control over the degree of hydrolysis and particle size of the product.
INQUITRE NOWSpecifications
| Appearance | Slightly Yellow grains solid |
|---|---|
| Total Solids wt%(min) | 98.0 |
| Degree of Hydrolysis (mole %) | 72.5.0±1.0 |
| Viscosity@20°C,4% solution (mPa.s) | 5.8±0.5 |
| Ash Content (as Na2O) wt% (max) | 0.3 |
| pH value | 4.5-7.0 |
Packing & Storage
|
Packing |
In 25kg paper bag. |
|---|---|
|
Storage |
Powder 20°C 2 years; Floccule 20°C 2 years. |
|
Shipping |
Room temperature 5-30℃ in China; may vary elsewhere |
Free Quote
Liwei PVA is one of the top 10 PVA factories and the top 100 strongest enterprises in anhui province.In 2010,Liwei PVA is evaluated as advanced and high technical company. We mainly deals in polyvinyl alcohol,PVA,PVA fiber and raw materials for producing PVA like vinyl acetate.
For samples, pricing, or more information, please call us at 0086-25-52397803 or mail to info@china-pva.net or fill out the following form. We will respond to you as soon as possible.
Tel: 0086-25-52397803
E-mail: info@china-pva.net
Frequently Asked Questions
GENERAL INFORMATION
PVOH®725
is a 72.5 mole%
hydrolyzed, polyvinyl
alcohol which has
been
specially developed
for use as a primary
suspending
agent
for vinyl chloride
suspension
polymerisation. Using
our exclusive batch
process which
in
that it allows more
efficient
control
over the degree
of hydrolysis and particle
size of
product.
PVOH®725 has lower
molecular
weight
and lower viscosity in the
grade.
It
was leading to
uniform PVC of good
morphology
over
the entire K value range.
Its high
level of conjugated
carbonyl groupings in the
polymer
chain give it superior
grain size
efficiency.
USES
Specifically, PVOH®725 is a suspending agent for suspension polymerisation of vinyl chloride monomer (VCM). The use of PVOH®725 requires no significant plant modification.
STORAGE
1.PVOH®725 should be stored
away
from
wet areas and naked
flames.
Ingress of
moisture should
be avoided to maintain
product
quality.
2.As supplied, the product
should
remain fit for use for 12
months
from
the date of
delivery. Beyond that
date, the
material may still be fit
for use,
but
we would advise that
it is good practice to
test the
material. As such, we
advise that
material stored for 12
months or more after
delivery
should
be tested before
use.
3.Aqueous solutions of
PVOH®725 if
stored for long periods at
elevated
temperatures are
prone to mould and
bacterial
attack.
FOR USED IN VCM SUSPENDING POLYMERISATION
PVOH®725 has an influence
on the
PVC
resin grain size
distribution,
porosity and bulk
density. This is due to
the
products
surface active nature,
reducing
the
interfacial tension
and enhancing distribution
of
initiator throughout the
batch.
The principal advantages
of using
PVOH®725 can be summarized
as
follows.
1.The desired PVC grain
size can
be
achieved using low levels
of
PVOH®725,
over a wide range
of polymerisation
temperatures, to
produce high bulk density
resins.
2.The PVC grains made with
PVOH®725
tend to be more spherical
such
that
higher bulk density
may be combined with
minimum
reduction
in porosity and with
optimum flow
characteristic.
3.The combination of
PVOH®725 and
PVOH®88 grades or
secondary
suspending
agent grades give
PVC resins of narrow grain
size
distribution and a good
balance of
bulk density and
porosity.
