6 Length Change of Polyester Resin Concrete YOSHIHIKO OHAMA, KATSUNORI DEMURA, and MASASHI KOMIYAMA
Downloaded by UNIV OF AUCKLAND on November 9, 2014 | http://pubs.acs.org Publication Date: November 27, 1979 | doi: 10.1021/bk-1979-0113.ch006
Department of Architecture, College of Engineering, Nihon University, Koriyama, Fukushima 963, Japan
In the past twenty years, polyester resin concrete has been widely studied as a construction material in the world. Polyester resin concrete is extensively used in both precast and cast-in-place applications in the field of construction works. In these practical applications styrene monomer is often added into polyester resin concrete as a diluent in order to improve chiefly its workability. It is well-known that polyester resin concrete posseses large setting shrinkage of about ten times that of portland cement concrete. The shrinkage is one of serious disadvantages to be improved in its precast product and cast-in-place applications. Although a number of investigations of polyester resin concrete have been reported till now, the papers concerning its length change are hardly found out in them . In this paper, polyester resin concrete using two types of unsaturated polyester resins as binding materials is prepared with various contents of styrene,shrinkage-reducing agent, catalyst and accelerator, and its early aged length change to 24 hours after mixing (strictly speaking, after adding catalyst to unsaturated polyester resin ) is studied. An experimental automatic apparatus for measuring the length change of polyester resin concrete is also reported. 1)
Materials Two types of commercially available orthophthalate-type unsaturated polyester resins (UP) were used as liquid resins, together with a 55% DMP(dimethyl phthalate) solution of methyl ethyl ketone peroxide (MEKPO) as a catalyst and a 8% mineral turpentine of cobalt octoate (CoOc) as an accelerator. UP-2 containing CoOc accelerator of 0.75phr (parts per hundred parts of resin). The properties of the unsaturated polyester resins are listed in Table I. Two types of commercially available shrinkage-reducing agents (SR) were used. They were produced by dissolving polystyrene in 0-8412-0523-X/79/47-113-067$05.00/0 © 1979 American Chemical Society
In Plastic Mortars, Sealants, and Caulking Compounds; Seymour, R.; ACS Symposium Series; American Chemical Society: Washington, DC, 1979.
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P L A S T I C
Table I .
Downloaded by UNIV OF AUCKLAND on November 9, 2014 | http://pubs.acs.org Publication Date: November 27, 1979 | doi: 10.1021/bk-1979-0113.ch006
Type of Polyester Resin
M O R T A R S ,
S E A L A N T S ,
A N D
C A U L K I N G
C O M P O U N D S
P r o p e r t i e s of Unsaturated Polyester Resins.
Acid Value
Specific Gravity (20°C)
Viscosity (20°C,cP)
Styrene Content (%)
UP-1
22.2
1.135
819
36.3
UP-2
25.9
1.160
1940
29.8
styrene, and s u p p l i e d making a s e t w i t h the unsaturated p o l y e s t e r resins. Styrene monomer (St) f o r i n d u s t r i a l use was used as a d i l u e n t . Commercially a v a i l a b l e calcium carbonate ("heavy"grade)was used as a f i l l e r , H a t s u k a r i crushed andésite (size,5-10 and 10-20mm) as coarse aggregate, and Abukumagawa r i v e r sand (size,1.2-5 and 1.2mm or f i n e r ) as f i n e aggregate. Their water contents were c o n t r o l l e d to be l e s s than 0.1%. The p r o p e r t i e s of the f i l l e r and aggregates are shown i n Table IE.
T a b l e IE.
P r o p e r t i e s o f F i l l e r and A g g r e g a t e s .
Type of F i l l e r and Aggregate
Grading (mm)
Specific Gravity (20°C)
Water Content (%)
Organic Impurities
