Copolymers, Polyblends, and Composites

37 Concrete-Polymer Composite Materials and

Downloaded by UNIV OF CALIFORNIA SANTA BARBARA on April 10, 2018 | https://pubs.acs.org Publication Date: June 1, 1975 | doi: 10.1021/ba-1975-0142.ch037

Their Potential for Construction, Urban Waste Utilization, and Nuclear Waste Storage MEYER STEINBERG Department of Applied Science, Brookhaven National Laboratory, Upton, N. Y. 11973

A range of concrete-polymer composite materials is under investigation. The old technology of hydraulic cement concrete is combined with the new technology of polymers. Polymer-impregnated precast concrete (PIC) is the most highly developed composite, and it exhibits the highest degree of strength and durability. Polymer concrete (PC), an aggregate bound with polymer, is potentially a most promising material for cast-in -place applications. PC with solid waste aggregate offers interesting possibilities for converting urban waste into commercially valuable construction materials. PIC and PC also show potential for immobilizing radioactive waste from the nuclear power industry for long-term engineered storage.

T

h e c o n c r e t e - p o l y m e r c o m p o s i t e m a t e r i a l s p r o g r a m at B r o o k h a v e n L a b o r a t o r y is d i r e c t e d at d e v e l o p i n g b o t h i m p r o v e d a n d n e w m a t e r i a l s b y c o m b i n i n g t h e a n c i e n t t e c h n o l o g y of h y d r a u l i c c e m e n t f o r m a t i o n w i t h t h e m o r e m o d e r n t e c h n o l o g y of p o l y m e r c h e m i s t r y . A c o n c r e t e - p o l y m e r c o m p o s i t e s is b e i n g i n v e s t i g a t e d . Polymer-Impregnated

Concrete

Materials

National concrete concrete r a n g e of

Development

P o l y m e r - i m p r e g n a t e d c o n c r e t e ( P I C ) is a p r e c a s t a n d c u r e d h y d r a t e d cement concrete w h i c h has been i m p r e g n a t e d w i t h a l o w viscosity m o n o m e r a n d p o l y m e r i z e d in situ. T h i s m a t e r i a l is t h e m o s t h i g h l y d e v e l o p e d c o m posite. T h e greatest i m p r o v e m e n t s i n structural a n d d u r a b i l i t y properties h a v e been attained w i t h P I C . W i t h conventional concrete (28-day w a t e r - c u r e d ) , compressive strengths c a n b e increased f r o m 5 0 0 0 p s i ( 3 5 2 k g / c m ) to 2 0 , 0 0 0 p s i ( 1 4 1 0 k g / c m ) . W a t e r a b s o r p t i o n is r e d u c e d b y 9 9 % , a n d f r e e z e - t h a w r e s i s t a n c e is e n o r m o u s l y i m p r o v e d . W i t h h i g h s i l i c a c e m e n t , s t r o n g b a s a l t i c aggregate, a n d h i g h temperature steam c u r i n g , strength c a n be increased f r o m 12,000 p s i ( 8 4 5 k g / c m ) to m o r e t h a n 3 8 , 0 0 0 p s i ( 2 6 3 0 k g / c m ) . T h e tensile 2

2

2

2

431

Platzer; Copolymers, Polyblends, and Composites Advances in Chemistry; American Chemical Society: Washington, DC, 1975.

432

COPOLYMERS,

POLYBLENDS,

A N D COMPOSITES

s t r e n g t h of P I C is a p p r o x i m a t e l y o n e - t e n t h t h e c o m p r e s s i v e s t r e n g t h s i m i l a r i n r e l a t i o n s h i p to c o n v e n t i o n a l c o n c r e t e . A m a x i m u m t e n s i l e s t r e n g t h of 3 5 0 0 p s i (238 k g / c m ) has been obtained w i t h the steam-cured concrete. I n steam-cured concrete, p o l y m e r loadings [ p o l y ( m e t h y l m e t h a c r y l a t e ) , ( P M M A ) ] are about 8 w t % of d r i e d c o n c r e t e . P I C a n d conventional concrete were tested for f r e e z e - t h a w effects ( F i g u r e 1 ) a n d f o r r e s i s t a n c e t o c h e m i c a l a t t a c k b y a c i d s (Figure 2).


2

Figure 1. Weight loss: PIC (6 wt % PMMA),

Freeze-thaw test 0.5%; control (conventional concrete), 26.5%

I n contrast to c o n v e n t i o n a l concrete, P I C exhibits essentially zero creep p r o p e r t i e s (see F i g u r e 3 ) . F u r t h e r m o r e , p o l y m e r i m p r e g n a t i o n t r a n s f o r m s c o n v e n t i o n a l concrete f r o m a plastic m a t e r i a l to essentially a n elastic m a t e r i a l w i t h at least a d o u b l i n g i n t h e m o d u l u s o f e l a s t i c i t y . T h i s is i n d i c a t e d b y t h e l i n e a r i t y of t h e s t r e s s - s t r a i n p l o t f o r P I C i n F i g u r e 4 . T h e a b i l i t y t o v a r y t h e s h a p e o f t h e s t r e s s - s t r a i n c u r v e offers s o m e i n t e r e s t i n g p o s s i b i l i t i e s f o r t a i l o r i n g desired properties of concrete f o r particular structural application. This m a y b e a c h i e v e d b y a d d i n g p l a s t i c i z e r s to t h e m o n o m e r s y s t e m s o r b y v a r y i n g t h e t y p e a n d s h a p e o f a g g r e g a t e (e.g., steel fiber a g g r e g a t e ) . P I C is f o r m e d b y d r y i n g c u r e d c o n v e n t i o n a l c o n c r e t e b y t h e m o s t c o n venient a n d economical processing technique (hot air, oven, steam, dielectric heating, etc.), d i s p l a c i n g the air f r o m the o p e n cell v o i d v o l u m e ( v a c u u m or monomer displacement a n d pressure), diffusing a l o w viscosity monomer


Concrete-Polymer

S T E I N B E R G


37.

Figure 2.

433

Composites

Resistance to chemical attack (15% HCl)

Weight loss: PIC, 7% after 497 days; control, 25% after 105 days

—ι L O A D E O AT 290* F 76

e

CYL* 2

F

e

290 F 76

30

60

90

Figure 3.

e

F

150 180 210 AGE UNDER LOAD - DAYS

1—

MONOMER S+TMPTMA S+TMPTMA Control Control

240

1 LOAD 7000 psi 7000 psi 2313 psi 2313 psi

270

Creep strain characteristics of PIC


SYMBOL

330


434

COPOLYMERS,

1000 COMPRESSIVE

Figure 4.

2000

3000

POLYBLENDS,

A N D COMPOSITES

4000

STRAIN (MICROINCHES/INCH)

Compressive stress-strain curve for PMMA-impregnated

concrete

Impregnated: elastic behavior; unimpregnated: plastic behavior

(

Copolymers, Polyblends, and Composites

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