Project no. 304
Biomass-Based Intumescent Coatings
K. Chen1,2, P. Ren1,2, Z. Li1,2, Z. Wang1,2, Y. Yang1,2
Supervisors: H. Wu2, Y. Zeng2
1Sino-Danish Center for Education and Research, University of Chinese Academy of
Sciences, #380 Huaibeizhuang, Huairou District, Beijing, 101400, China
2Department of Chemical and Biochemical Engineering, Technical University of Denmark,
Søltofts Plads, Building 229, DK-2800 Kongens Lyngby, Denmark
Intumescent coating is a fire protection material which consists of acid source, carbon
source, and blowing agent. One application of intumescent coating is building surface
painting. When exposed to high temperature, it can expand to a porous char layer which
isolates heat and oxygen and thereby holds off the building from collapsing. The
conventional carbon source of intumescent coatings is pentaerythritol, which is neither
renewable nor environmentally friendly. Biomass, which is rich in the content of -OH group,
is a potential carbon source of intumescent coating.
Environmentally friendly intumescent coating is expected to be synthesized with biomass as
carbon source, which is a low-cost option when biomass waste is the candidate. Meanwhile,
it provides an alternative of treating biomass waste. Thermogravimetric analysis and fireresistance
tests are expected to evaluate the feasibility of this thought.
Biomass, including coffee grounds, tea leaves, wheat straw and biomass waste slurry will be
used for coating synthesis, respectively. The biomass is milled in a knife mill, then the milled
biomass particles and other typical ingredients of intumescent coatings are mixed in a
disperser. Once it mixed well, the mixture is applied to a steel plate with the dimension of 60
ⅹ60ⅹ3 mm, followed by curing for 24 h at room temperature.
Thermogravimetric analysis (TGA) is conducted for evaluating the thermal decomposition of
these coatings, using a Netzsch Jupiter F1 STA. The temperature range for the tests is from
50 to 1000 ℃, with a heating rate of 10 ℃/min under atmosphere. A lab-scale oven is used
for fire testing by applying the coatings on a steel plate. The temperature of the backside of
the plate is measured by a type K thermocouple.
The experiments are in progress, we expect that fire testing will demonstrate the fireresistance
performance of the intumescent coatings with biomass as char former. The
addition of biomass in the coating may reduce the temperature of the substrate by lowering
the thermal conductivity of the intumescent chars. Additionally, we expect to see the
presence of pores in the char layer, and expansion of the coating thickness after fire testing.