Non-reactive additives for fiber coatings
The present invention relates to a curable composition having an oligomer, at least one monomer, and an amount of a substantially non-reactive oligomeric additive. The substantially non-reactive oligomeric additive is present in an amount effective to yield a cured product having a fracture toughness value that is higher than the fracture toughness value of a cured product of an otherwise identical composition lacking the non-reactive oligomeric additive. The present invention also relates to coated optical fibers, optical ribbons or bundles, and telecommunication systems having the curable composition.
1. A curable composition comprising:
an oligomer;
at least one monomer; and
an amount of a substantially non-reactive oligomeric additive that is effective to yield a cured product having a fracture toughness value that is higher than the fracture toughness value of a cured product of an otherwise identical composition lacking the non-reactive oligomeric additive, wherein the substantially non-reactive oligomeric additive has a structure or average structure according to formulae (I), (II), or (III)
CAP 1 —RT′—OOC—NH—R 1 —NH—COO—RT′—CAP 1 (I)
R M —[OOC—NH—R A —NH—COO—RT′—CAP 1 ] n (II)
CAP 1 —RT′—OOC—NH—R 1 —NH—[COO—R 2 —OOC—NH—R 1 —NH] w —COO—RT′—CAP 1 (III)
wherein RT′—CAP 1 is the reaction product of a moiety (RT) having a reactive terminus and a capping moiety comprising a functional group that reacts with the reactive terminus, wherein RT′—CAP 1 has a non-reactive terminus,
R 1 is a polyisocyanate core moiety substantially free of urethane bonds,
R A is R 1 or —R 1 —(NH—COO—R C —OOC—NH—R 1 ) t — where R C is a polyol-containing core moiety and t has an average value in the range of 0 to about 4,
R M is a core moiety having an average functionality of n, where n is greater than 2.2,
R 2 includes either at least one crystallizable polyol-derived moiety or at least one cyclic rigid moiety, and
w is greater than zero.
2. The composition according to claim 1 , wherein the curable composition is radiation curable.
3. The composition according to claim 1 , wherein the substantially non-reactive oligomeric additive comprises up to about 20% of the composition.
4. The composition according to claim 1 , wherein the substantially non-reactive oligomeric additive comprises up to about 10% of the composition.
5. The composition according to claim 1 , wherein the cured product of the curable composition is characterized by a fracture toughness value of at least about 1.1 Mpa·m 1/2 .
6. The composition according to claim 1 , wherein the cured product of the curable composition is characterized by a defect sensitivity value (a*) greater than about 200 μm.
7. The composition according to claim 1 , wherein the cured product of the curable composition is characterized by a fracture toughness value of at least about 1.1 Mpa·m 1/2 and a defect sensitivity value (a*) greater than about 200 μm.
8. The composition according to claim 1 , wherein the cured product of the curable composition is characterized by a Young's modulus of at least about 1200 MPa.
9. The composition according to claim 1 , wherein the cured product has a Young's modulus that is substantially the same as the Young's modulus of the cured product of an otherwise identical composition lacking the non-reactive oligomeric additive.
10. The composition according to claim 1 , wherein the cured product has a glass transition temperature (Tg) that is substantially the same as the glass transition temperature (Tg) of the cured product of an otherwise identical composition lacking the non-reactive oligomeric additive.
11. A curable composition comprising:
an oligomer;
at least one monomer; and
an amount of a substantially non-reactive oligomeric additive that is effective to yield a cured product having a fracture toughness value that is higher than the fracture toughness value of a cured product of an otherwise identical composition lacking the non-reactive oligomeric additive, wherein the substantially non-reactive oligomeric additive has a structure or average structure according to formulae (IV), (V), or (VI)
CAP 2 —X—OCN—R 1 —NCO—X—CAP 2 (IV)
R M —[OOC—NH—R A —NCO—X—CAP 2 ] n (V)
CAP 2 —X—OCN—R 1 —NH—[COO—R 2 —OOC—NH—R 1 —NH] W —CO—X—CAP 2 (VI)
wherein
CAP 2 —X— is a capping moiety having a non-reactive terminus,
X is S, O, or N,
R 1 is a polyisocyanate core moiety substantially free of urethane bonds,
R A is R 1 or —R 1 —(NH—COO—R C —OOC—NH—R 1 ) t — where R C is a polyol-derived core moiety and t has an average value in the range of 0 to about 4,
R M is a core moiety having an average functionality of n, where n is greater than 2.2.
R 2 includes either at least one crystallizable polyol-containing moiety or at least one cyclic rigid moiety, and
w is greater than zero.
12. The composition according to claim 11 , wherein the substantially non-reactive oligomeric additive comprises up to about 10% of the composition.
13. The composition according to claim 11 , wherein the cured product of the curable composition is characterized by a fracture toughness value of at least about 1.1 MPa·m 1/2 .
14. The composition according to claim 11 , wherein the cured product of the curable composition is characterized by a defect sensitivity value (a*) greater than about 200 μm.
15. The composition according to claim 11 , wherein the cured product of the curable composition is characterized by a Young's modulus of at least about 1200 MPa.
16. The composition according to claim 11 , wherein the cured product has a Young's modulus that is substantially the same as the Young's modulus of the cured product of an otherwise identical composition lacking the non-reactive oligomeric additive.