Polymer Emulsion Adhesives Enter Sound Development Stage


By Gong Beifan


Due to its advantages such as good adhesive,
environment-friendly and economical efficiency, polymer
emulsion adhesive is acclaimed by the customers in the world.  
Polymer emulsion adhesives include polyacrylate emulsion (PAE),
polyvinyl acetate (PVAc) emulsion, vinyl acetate-ethylene
copolymer (VAE) emulsion, and polyurethane (PU) emulsion and
rubber type emulsion that have been in the stage of research and
development in China.




Rapid development of polymer emulsion adhesives


    1. Output increased rapidly


The production of polymer emulsion in China has achieved a
considerable progress in recent years. The annual output growth
of polymer emulsion adhesive in China was 20% from 2001 to 2004
and being the highest level in the world. The output of major
polymer emulsion adhesive in China was 1.483 million tons in 2004,
an increase of 16.6% over 2003.It is expected that the annual
output growth of emulsion polymer adhesive will be 12-15%, and
the output of major emulsion polymer adhesive will 3.0 million
tons in 2010.


     2. Polymerization equipment tends to be large scale


Some large and medium producers are gradually expending the
volume of polymerization kettle to 13-20 m3 or more from several
cubic meters. Wing Tai(Zhongshan) Co., Ltd. and Foshan Yida
Adhesive Co., Ltd. has built a polymerization kettle with a
volume of 38 m3, and the production is normal and the economic
benefit has achieved. Shanghai Eastern Rohm and Hass Co., Ltd.
can produce 36 tons emulsion product at one time in the
polymerization kettle with a volume of 25 m3 using
semi-continual polymerization process. The 7 m3 polymerization
kettle with domestic intellectual property has been used in
Shanxi Sanwei Group. The application of these new equipment has
not only increased the output, saved the energy and resource,
but also improved the product quality.


     3. Supply shortage of main raw material


The output of vinyl acetate (VAc) in China was 960 000 tons in
2004, and import amount was around 147 000 tons. The output and
import amount of butyl acrylate was 182 500 tons and 230 000 tons,
respectively in 2004. Besides, the raw materials such as
tert-ethylene carbonate and polysiloxane not only have high
prices, but also short of supply, and the development of new
emulsion polymers with high performance and quality in China
have been seriously restricted.




Production of major polymer emulsion adhesives


      1. PAE


PAE is mainly used in pressure-sensitive adhesive product,
coatings, construction material, textile, nonwovens, package,
paper processing, communication and transportation sectors. The
output of PAE in China was 820 000tons in 2004, an increase of
20.6% over 2003, being the largest output in polymer emulsion
sector.
   There are many PAE producers in China, and mainly distributed
in Shanghai, Beijing, Guangdong and Jiangsu. However, the number
of the enterprises with large scale and high production level
are less than 50.


      2. PVAc emulsion


There are more than 200 PVAc emulsion producers in China, but
only 6 producers with capacity over 10 000t/a and 2 producers
with capacity over 50 000t/a. The output of PVAc emulsion in
China was 560 000 tons in 2004, a rise of 12.0% over the previous
year.


      3.VAE emulsion


The application fields of VAE emulsion in China has extended from
the sectors of carpet, cigarettes, construction materials and
textile to quite a few sectors such as composite materials,
packing, shoe making, wood processing and waterproof materials.
The output of VAE emulsion in China was 103 000 tons in 2004,
an increase of 12.0% over 2003. According to the projection made
by China Adhesive Industry Association, due to the high economic
growth, the demand of VAE emulsion in China will be over 200 000
tons in 2010.


      4. Water base adhesive


Water base adhesives are produced through physical method or
chemical reaction with VAE emulsion, PVAc emulsion, casein, and
cross-linking agent as raw materials, and extensively used in
construction, wood processing, paper product, textile, non
woven fabric and printing and bonding sectors. The sale amount
of water base adhesives was around 80 000 tons in 2004.




Development Trend


      1. Three-capital enterprises develop rapidly


Three-capital enterprises (those run with foreign funds only,
Chinese-foreign joint ventures and cooperative enterprises) in
China will still maintain a rapid development trend in future.
With the production scale expanding, investment increase and the
increase of high technical products, the three-capital
enterprises will hold a very important position in the domestic
polymer emulsion market, and greatly promote the development of
domestic polymer emulsion and the improvement of production
level and product grade.


      2. Production is being concentrated in large-scale
enterprises


There are more than 500 polymer emulsion producers in China. Most
producers have small production scale, low technique level, low
product quality and environment pollution, and can not actualize
sustained development. With the market competition becoming
fiercer and the higher requirement on the product quality, the
small-scale enterprises will be eliminated. According to the
statistics made by China Adhesive Industry Association, the
number of the polymer emulsion enterprises to be suspended
accounted for around 15% of the total in 2004. The production
of polymer emulsion is being concentrated in large-scale
enterprises.


Table 1 Output of the Major Polymer Emulsion in China in Recent
Years  
(thousand tons)
Year            2001    2002    2003    2004    2010
(projected)
PAE             420     560     680     820     1 330
PVAc emulsion   380     420     500     560     1 100
VAE emulsion    59      71      92      103     240
Total           859     1 051   1 272   1 483   2 670
Source: CNCIC Chemdata


Table 2 Major PAE Producers in China in 2004  
(thousand t/a)
Producer                             Capacity
Beijing Eastern Rohm and Hass Co.       30
Shanghai Eastern Rohm and Hass Co.      30
Shanghai BASF Dyestuff & Che