Polyisobutylene Sector Needs to Expand Applications

By Yu Minglei, PetroChina East China Design Institute Co., Ltd.,
Li Tingqiang, PetroChina Jilin Petrochemical Co., Ltd. Acrylonitrile Plant


China’s polyisobutylene (PIB) capacity in 2016 was around 169 kt/a. In China, PIB varieties are classified in one dimension as either low molecular weight PIB or medium molecular weight PIB, and at the same time in another dimension, as industrial grade or food grade. The main producers of low molecular weight, high reactivity PIB are Nanjing BASF-YPC Co., Ltd. and Jilin Petrochemical Co., Ltd. The major producer of medium molecular weight PIB is Shandong Yuhuang Chemical (Group) Co., Ltd., operating a 20 kt/a PIB unit. Both industrial-grade and food-grade varieties are produced by Hangzhou Shunda Group Polymer Material Co., Ltd. Table 1 shows the major PIB producers in China in 2016.

Table 1    Major PIB producers in China, 2016

Producer    Capacity (kt/a)    Product variety    Remarks
Nanjing BASF-YPC Co., Ltd.    50    High reactivity PIB    Production started in November 2011. BASF process is used.
Jinzhou Jinex Lubricant Additives Co., Ltd.    30    Low molecular weight PIB    Mixed C4 is used as feedstock.
Jilin Petrochemical Co., Ltd. Fine Chemicals Plant    20    High reactivity PIB    Boron series (BF3) catalyst system is used.
    2 (temporarily shut down)    Medium molecular weight PIB    The 4.5 kt/a low molecular weight PIB unit is renovated to a 2 kt/a medium molecular weight PIB unit. Boron series (BF3) catalyst system is used.
Shandong Yuhuang Chemical (Group) Co., Ltd.    20    Medium molecular weight PIB    The product molecular weight is 30 000-100 000. The unit was completed in 2013.
Shandong Hongrui Petrochemical Co., Ltd.    10    Low molecular weight PIB    Trial run was conducted in December 2008. The medium molecular weight PIB unit has expanded its capacity to 10 kt/a (both industrial-grade variety and food-grade variety can be produced).
    10    Medium molecular weight PIB    
Lanzhou Luborun Lanlian Additives Co., Ltd.    12    Low molecular weight PIB    Mixed C4 is used as feedstock.
Hangzhou Shunda Group Polymer Material Co., Ltd.    6    Medium molecular weight  PIB (both industrial grade and food grade)    Either aluminum series catalyst system or boron series catalyst system can be used. Aluminum series is used today.
    4    Low molecular weight PIB (food grade)    
Xinjiang Xinfeng Co., Ltd.    5    Low molecular weight PIB    Mixed C4 is used as feedstock.
Total    169        


Consumption increase coming

High reactivity PIB (HRPIB) capacity in 2016 was 80 kt/a. Oversupply is quite evident.
With domestic oil product quality constantly being improved, a product made from PIB, polyisobutylene amine will likely be added to various oil products, as it is an excellent oil product modifier. So demand for HRPIB is expected to increase drastically, at an annual rate of 10%.
In the domestic market, medium molecular weight PIB comes mainly from BASF of Germany, Hangzhou Shunda Group Polymer Material Co., Ltd. and Shandong Yuhuang Chemical (Group) Co., Ltd. Food-grade medium molecular weight PIB is an excellent raw material for the gum base of chewing gums and can also be used to make medical plasters.
Owing to the rapid development of the market for adhesive insulation for glass (mostly windows), applications of medium molecular weight PIB have already quickly expanded from high-grade buildings to conventional buildings, air-conditioned trains, air-conditioned passenger cars, refrigerators and display cabinets. In sealing strips, the usual content of medium molecular weight PIB is around 20%. Insulating glass has a dual sealing structure. The content of medium molecular weight PIB in the first seal can exceed 40%. As requirements for energy conservation and environmental protection are increasingly stringent, the consumption of medium molecular weight PIB will increase constantly, and the market prospects are extremely bright.
Downstream, the product chain of PIB also includes combustion property modifiers, polymer modifiers, gum-based foods and food packages. With the ongoing development of sectors such as special sealing materials and foods demand for medium molecular weight PIB will likely be promoted in the next few years. Table 2 shows the supply/demand of PIB in China during 2011-2016.

Table 2    PIB supply/demand in China, 2011-2016   (t)

Year    Output    Apparent consumption
2011    98 475    126 719
2012    105 180    129 925
2013    49 200    71 400
2014    64 000    85 473
2015    50 000    64 371
2016    56 000    88 512


Table 3  China’s foreign trade in PIB, 2008-2016   (t)

Year    Import volume    Export volume
2008    12 047    12 842
2009    19 000    6 683
2010    28 233    4 876
2011    34 234    5 990
2012    28 752    4 007
2013    27 024    4 824
2014    27 946    6 473
2015    26 444    12 073
2016    39 301    6 789


Foreign trade

In 2016, market demand recovered, and import of PIB increased drastically, while export returned to 2014’s level. Table 3 shows China’s PIB import/export during 2008-2016 (including PIB in primary form and in other forms such as boards, sheets and belts).