the chemistry and applications of benzoxazines reporter: meng wei wang advising prof: ru jong jeng...

The Chemistry and Applications of Benzoxazines

Reporter: Meng Wei Wang

Advising Prof: Ru Jong Jeng

Hatsuo Ishida and Tarek Agag, Handbook of Benzoxazine Resins

Outline

Chemistry of benzoxazines Synthesis Ring-opening mechanisms

Recent development of benzoxazines Monomeric benzoxazines Main chain type Side chain type

Another applications for benzoxazine resins Conclusions

Benzoxazine (Bz) resins

1. Low cost of raw materials 5. Low water absorption2. No need for harsh catalysts 6. Low surface energy 3. No by-product 7. Superior electrical properties4. Small shrinkage in curing 8. Considerable flexibility in the molecular design.

5,6Wang, C.-F., et al ,Angew. Chem. Int. Ed. 2006, 45, 2248.7Ishida, H., et al ,J. Polym. Sci. Part A: Polym. Chem. 1994, 32, 1121.

R1

NOR2

R1

OH

N

R2n

Benzene

Oxazine

Polybenzoxazine themosets.

How to synthesize benzoxazines?

One-pot procedure (Traditional procedure)R1

N

O

R1 OH + 2 CH2O + H2N

n NH2 + (CH2O)n70oC

n

NHCH2OH

NHCH2OH

3N

N N+ 3 H2O

70oC

Brunovska, Z.; Liu, J.-P.; Ishida, H. Macromol. Chem. Phys.1999, 200, 1745.

Mechanism:

N N

NN

OH OH

1/3

N

OH

OH

NOH

N

OO

H

HO H

+ HO

H

Two-pot procedure

XH2N NH2 C

O

HH4 OH2

XN NO

O

dioxane

XHN NHHO

OH

XH2N NH2C

OHO

HXN N

HO

OH

C

H

H

S

O

O

CH3

CH3

O O

OO

2DMF

NaBH4

ethanol

CHCl3

C

O

HH

X (gel or insoluble product)

X =

for(1, 5, 9, 13)

for(2, 6, 10, 14)

for(3, 7, 11, 15)

for(4, 8, 12, 16)

(1-4) (5-8)

(9-12)

(13-16)

Lin. C.H., et al ,Polymer 2008, 49, 1220

Ring-opening mechanism of benzoxazines

What is the mechanism of polymerization?

Type I - Phenoxy structure

Ishida, H., et al , Macromolecules 2000, 33, 2839.

Type II – Phenolic structure

Ishida, H., et al , Macromolecules 2000, 33, 2839.

Main chain rearrangement

Endo, T., et al , Macromolecules 2008, 41, 9030.

The acceleration of benzoxazine polymerization (I)

Andreu, R. et al., J. Polym. Sci., Part A: Polym. Chem. 2008, 46, 3353.

When R1 is electron-withdrawing group → Decrease in the polymerization temp.When R2 is electron-withdrawing group → Increase in the polymerization temp.

Gu, Y. et al., J. Polym. Sci., Part A: Polym. Chem. 2011, 49, 1443.

The acceleration of benzoxazine polymerization (II)

Endo, T., Macromolecules 2010, 43, 1185.

Ronda, J. C., et al., J. Polym. Sci., Part A: Polym. Chem. 2008, 46, 3353.

Ishida, H., Macromolecules 2012, 45, 8119.

Outline

Chemistry of benzoxazines Synthesis Ring-opening mechanisms

Recent development of benzoxazines Monomeric benzoxazines Main chain type Side chain type

Another applications for benzoxazine resins Conclusions

Monomeric benzoxazines (I)

NOR

R'

R'

OH

N

R

R'

OH

n

Lin. C.H., et al ,Polymer 2008, 49, 1220

Sample Tg (oC) Td (oC) Char yield (%)

P(13) 208 425 52

P(F-a) 155 314 49

Poor mechanical property

Bisphenol type Diamine type

Monomeric benzoxazines (II)

Curing

Sample Tg (oC)

PPa 161

PP-appe 251

PBa 171

PB-appe 318

Takeichi, T., et al, Macromolecules 2001, 34, 7257.

Lin, C. H., et al, J. Polym. Sci. Part A: Polym. Chem. 2010, 48, 4555.

Main chain type polybenzoxazine precursors

Takeichi, T., et al, Polymer 2005, 46, 12172.

Lin. C.H., et al ,Polym. Chem. 2012, 3, 935

Side chain type polybenzoxazine precursors

Sample Tg (oC)

Va/DGEBA 174

VBa/DGEBA 143

Kimura. H., et al , J. Appl. Polym. Sci. 2001, 79, 555

Endo. T., et al , J. Polym. Sci. Part A: Polym. Chem. 2011, 49, 3174

Outline

Chemistry of benzoxazines Synthesis Ring-opening mechanisms

Recent development of benzoxazines Monomeric benzoxazines Main chain type Side chain type

Another applications for benzoxazine resins Conclusions

Another applications for benzoxazine resins (I)

Takeichi, T., et al, J. Polym. Sci. Part A: Polym. Chem. 2001, 39, 2633.

Ishida, H., et al., Polym. Chem. 2011, 49, 4335.

Takeichi, T., et al, Polymer 2008, 49, 1173.

Another applications for benzoxazine resins (II)Ishida, H., et al., Macromolecules 2012, 45, 8991.

Endo, T., et al .ACS Macro Lett. 2013, 2, 1.

Conclusions

Considerable flexibility in the molecule-design Crosslink No by-product

Future work More functionality Brittle Ring-open temperature

R1

NOR2

R1

OH

N

R2n

Thanks for your attention.