Alkyl ether substituted cyclotrisiloxanes and preparation method thereof
A new class of cyclotrisiloxanes having alkyl ether substituents on one, two, or three of the ring silicon atoms and a method for their preparation are provided. These compounds undergo living anionic ring-opening polymerization to generate unique polymer structures. A new class of hydridosilylethylcyclotrisiloxanes is also described.
1. A cyclotrisiloxane wherein one, two, or three of the ring silicon atoms has a polyalkyleneoxide substituent comprising two or more ethylene oxide groups, wherein each polyalkyleneoxide substituent is bonded to the ring silicon atom by a silylalkyl linkage or a siloxanylethyl linkage.
2. The cyclotrisiloxane according to claim 1 , having formula (1):
3. The cyclotrisiloxane according to claim 1 , having formula (2):
4. The cyclotrisiloxane according to claim 1 , having formula (3), wherein m is 1 to about 10:
5. A cyclotrisiloxane having formula (4):
wherein m is an integer from 1 to about 10, n is an integer of at least 0, R is methyl, ethyl, or butyl, and R′ is H, an alkyl or an aryl group.
6. The cyclotrisiloxane according to claim 1 , wherein each polyalkyleneoxide bonds to the ring silicon by a silylalkyl linkage, wherein the alkyl group has 2 to 8 carbon atoms.
7. The cyclotrisiloxane according to claim 1 , wherein each polyalkyleneoxide substituent bonds to the ring silicon by a siloxanylethyl linkage.
8. A cyclotrisiloxane wherein one, two, or three of the ring silicon atoms has a polyalkyleneoxide substituent, wherein each polyalkyleneoxide substituent is bonded to the ring silicon atom by a silylalkyl linkage or a siloxanylethyl linkage, wherein each polyalkyleneoxide substituent is an alkoxyalkylenoxypropyl substituent, the alkoxy group is methoxy, ethoxy, or butoxy, and the alkylenoxy group is ethylenoxy or propylenoxy.
9. A cyclotrisiloxane wherein one, two, or three of the ring silicon atoms has a polyalkyleneoxide substituent, wherein each polyalkyleneoxide substituent is bonded to the ring silicon atom by a silylalkyl linkage or a siloxanylethyl linkage, wherein each polyalkyleneoxide substituent is an alkoxyalkoxyalkylenoxypropyl substituent, wherein each alkoxy group is independently methoxy, ethoxy, or butoxy, and wherein the alkylenoxy group is ethylenoxy or propylenoxy.
10. A cyclotrisiloxane wherein one, two, or three of the ring silicon atoms has a polyalkyleneoxide substituent, wherein each polyalkyleneoxide substituent is bonded to the ring silicon atom by a silylalkyl linkage or a siloxanylethyl linkage, wherein each polyalkyleneoxide substituent is alkoxy(alkylenoxy) m propyl, wherein the alkoxy group is methoxy, ethoxy, or butoxy, the alkylenoxy group is ethylenoxy or propylenoxy, and m is 1 to about 10.
11. A hydridosilylethylcyclotrisiloxane having formula (1), wherein R 1 , R 2 , and R 3 are independently selected from the group selected from methyl and dimethylsilylethyl, wherein at least one of R 1 , R 2 , and R 3 is dimethylsilylethyl:
12. The hydridosilylethylcyclotrisiloxane according to claim 11 , having formula (5):
13. The hydridosilylethylcyclotrisiloxane according to claim 11 , having formula (6):
14. A method of preparing a cyclotrisiloxane wherein one, two, or three of the ring silicon atoms has a polyalkyleneoxide substituent comprising two or more ethylene oxide groups, wherein each polyalkylene oxide substituent is bonded to the ring silicon atom by a silylalkyl linkage or a siloxanylethyl linkage, the method comprising hydrosilylating a hydride functional cyclotrisiloxane with an allyl ether of an oligo- or poly-alkylene oxide to yield a cyclotrisiloxane according to claim 1 .
15. The method according to claim 14 , wherein the hydride functional cyclotrisiloxane has formula (I), wherein R 1 , R 2 , and R 3 are independently selected from the group selected from methyl and dimethylsilylethyl, wherein at least one of R 1 , R 2 , and R 3 is dimethylsilylethyl:
16. The method according to claim 14 , wherein the hydride functional cyclotrisiloxane has formula (5):
17. The method according to claim 14 , wherein the hydride functional cyclotrisiloxane has formula (6):
18. The method according to claim 14 , wherein the hydride functional cyclotrisiloxane has formula (7):
19. The method according to claim 14 , wherein the hydride functional cyclotrisiloxane has formula (8):