硅氧烷索引政策
常规信息
通过烷氧基硅烷或卤代硅烷水解聚合制备的硅氧烷，通常在 CASM/CAplusSM 数据库中以受控词标题 SILOXANES AND SILICONES 进行索引，且不进行聚合物注册。仅以结构重复单元 (SRU) 描述的硅氧烷也以此标题索引，且不进行聚合物注册。
自 1994 年 6 月（第 121 卷）起，索引策略进行了修改和放宽，允许对之前仅作为 CA 数据库中文本术语处理的硅氧烷进行结构表示和机器注册。CAS 认识到，这些侧重于基于单体的聚合物注册的政策变更，并不能完全满足用户对 SRU 类型注册所能提供的结构特异性的需求。我们希望在未来增强 CAS REGISTRYSM 功能时提供这种特异性。下述变更提供了目前可注册的结构，从而将结构信息从 CA 数据库转移到 REGISTRY 数据库，我们认为这提高了可检索性。
以下领域受这些变更影响：
- 通过烷氧基硅烷水解聚合制备的硅氧烷。
- 通过卤代硅烷水解聚合制备的硅氧烷。
- 仅以 (-O-SiRR'-)n（R, R' = 一价基团）类型的单单元 SRU 描述的硅氧烷。
- 仅以 (-O-SiR2-)x(-O-SiR'2-)y 或 (-R2SiO-)x(-R'SiO1.5-)y（R,R' = 一价基团）类型的多单元 SRU 描述的硅氧烷。
- 通过烷氧基硅烷或氯代硅烷水解聚合制备的倍半硅氧烷。
- 通过四烷氧基硅烷与含有有机部分的烷氧基硅烷（可能是三烷氧基甲硅烷基封端的有机聚合物）水解聚合（溶胶-凝胶工艺）制备的陶瓷聚合物（有机-无机杂化网络）。
- 硅氧烷 SRU 的端基。
- 含有硅氧烷组分的共聚物。
- 硅氧烷和倍半硅氧烷的商品名。
- 硅橡胶。
政策变更的一个重要方面是，对于通过卤代硅烷水解聚合制备的硅氧烷和倍半硅氧烷，在结构表示中接受水。另一个重要方面是，在从 (3) 和 (4) 类型的硅氧烷 SRU 表示提供基于单体的聚合物注册时，接受羟基硅烷作为标准单体假设。
另请注意，当可以进行聚合物注册时，受控词标题 SILOXANES AND SILICONES 和 SILSESQUIOXANES 下不再常规提供硅氧烷主链上取代基的描述。此类信息反映在 Registry 文件和化学物质索引条目的结构表示中。
1. 基于烷氧基硅烷的硅氧烷
来自烷氧基硅烷水解聚合的硅氧烷在 CA 数据库中获得基于单体的聚合物注册，并在受控词标题 SILOXANES AND SILICONES 下获得聚合物类别条目。当 SRU 为单单元类型时，会额外增加一个条目。
示例 1：由 Me2Si(OMe)2 水解聚合制得的硅氧烷。
Registry 文件：Silane, dimethoxydimethyl-, homopolymer [25498-04-8]
Poly[oxy(dimethylsilylene)] [9016-00-6]
CA 文件：Siloxanes and Silicones
---
示例 2：由 Me2Si(OMe)2 与
Ph2Si(OMe)2 水解共聚制得的硅氧烷。
Registry 文件：Silane, dimethoxydimethyl-, polymer with
dimethoxydiphenylsilane
CA 文件：Siloxanes and Silicones
2. 基于卤代硅烷的硅氧烷
对于来自卤代硅烷（主要是氯代硅烷）水解聚合的硅氧烷，水被包含在聚合物注册中，并通过使用术语“hydrolytic”（例如，Silane, dichlorodimethyl-, homopolymer, hydrolytic）纳入聚合物名称中。这些措施对于将硅氧烷与同样由氯代硅烷制备但处于非水解反应条件下的聚硅烷（例如，Silane, dichlorodimethyl-, homopolymer）区分开来是必要的。针对基于单体的聚合物进行条目登记，并在受控词标题 SILOXANES AND SILICONES 下进行登记。当 SRU 为单单元类型时，会额外增加一个条目。
示例 1：由 Me2SiCl2 水解聚合制得的硅氧烷。
Registry 文件：Silane, dichlorodimethyl-, homopolymer, hydrolytic
[158158-00-0]
Me
|
(Cl-Si-Cl . H2O)x
|
Me
MF (C2H6Cl2Si . H2O)x
Poly[oxy(dimethylsilylene)] [9016-00-6]
CA 文件：Siloxanes and Silicones
---
示例 2：由 Me2SiCl2 与
Ph2SiCl2 水解共聚制得的硅氧烷。
Registry 文件：Silane, dichlorodimethyl-, polymer with dichlorodiphenylsilane,
hydrolytic [156665-92-8]
Me Ph
| |
(Cl-Si-Cl . Cl-Si-Cl . H2O)x
| |
Me Ph
MF (C12H10Cl2Si . C2H6Cl2Si . H2O)x
CA 文件：Siloxanes and Silicones
3. 单单元硅氧烷 SRU
仅以单单元 SRU 描述的硅氧烷在 SILOXANES AND SILICONES 下以 SRU 条目和受控词条目进行索引。此外，通过假设羟基硅烷为单体，进行基于单体的聚合物条目登记。
示例：作者表示为 (-OSiMe2-)n 或
“poly(dimethylsiloxane)”且无制备信息及
未指定端基的硅氧烷。
Registry 文件：Poly[oxy(dimethylsilylene)] [9016-00-6]
Silanediol, dimethyl-, homopolymer [31900-57-9]
（基于假设单体的聚合物）
CA 文件：Siloxanes and Silicones
4. 多单元硅氧烷 SRU
仅以 (-O-SiR2-)x(-O-SiR'2-)y 或 (-R2SiO-)x(-R'SiO1.5-)y（R,R' = 一价基团）类型的多单元 SRU 描述的硅氧烷不能注册为 SRU。它们在 SILOXANES AND SILICONES 下以受控词条目进行索引，并通过假设羟基硅烷为单体进行基于单体的聚合物条目登记。
示例：作者表示为 (-OSiMe2-)x(-OSiPh2-)y
且未提供制备信息的硅氧烷。
Registry 文件：Silanediol, dimethyl-, polymer with diphenylsilanediol
[156048-34-9]
（基于假设单体的聚合物）
CA 文件：Siloxanes and Silicones
5. Silsesquioxanes
For silsesquioxanes (siloxanes with repeating RSiO1.5 units), entries are made at the monomer-based polymer [based on the actual or assumed (hydroxysilane) monomer] and at the controlled-term heading SILSESQUIOXANES. Ladder-type SRU entries are made for silsesquioxanes represented by a single RSiO1.5 repeat unit, e.g., when R = Me.
Example 1: Me silsesquioxane from hydrolytic polymerization of MeSi(OMe)3.
Registry File: Silane, trimethoxymethyl-, homopolymer [25498-03-7]
Poly[(1,3-dimethyl-1,3:1,3-disiloxanediylidene)-
1,3-bis(oxy)] [153315-80-1]
Me
|
--O-Si--
|
( O )
| n
--O-Si--
|
Me
MF (C2H6O3Si2)n
CA File: Silsesquioxanes
---
Example 2: Me silsesquioxane from hydrolytic polymerization of MeSiCl3.
Registry File: Silane, trichloromethyl-, homopolymer, hydrolytic [156894-09-6]
Cl
|
(Cl-Si-Cl . H2O)x
|
Me
MF (CH3Cl3Si . H2O)x
Poly[(1,3-dimethyl-1,3:1,3-disiloxanediylidene)-
1,3-bis(oxy)] [153315-80-1]
Me
|
--O-Si--
|
( O )
| n
--O-Si--
|
Me
MF (C2H6O3Si2)n
CA File: Silsesquioxanes
---
Example 3: A silsesquioxane represented as (-MeSiO1.5-)n with no
preparative information.
Registry File: Silanetriol, methyl-, homopolymer [104133-11-1]
(polymer based on assumed monomer)
Poly[(1,3-dimethyl-1,3:1,3-disiloxanediylidene)-
1,3-bis(oxy)] [153315-80-1]
Me
|
--O-Si--
|
( O )
| n
--O-Si--
|
Me
MF (C2H6O3Si2)n
CA File: Silsesquioxanes
6. Ceramers
Ceramers are hybrid organic-inorganic networks obtained by the sol-gel process based on the hydrolytic polycondensation of tetraalkoxysilanes with alkoxysilane-containing organic moieties. Such networks are indexed as monomer-based polymers when the components are specified and all are involved in the polycondensation.
Example: A ceramer prepared from (EtO)4Si and (EtO)3Si[O(CH2)4]
nOSi(OEt)3 using the sol-gel process.
Registry File: Silicic acid (H4SiO4), tetraethyl ester, polymer
with .alpha.-(triethoxysilyl)-.omega.-[(triethoxysilyl)oxy]-
poly(oxy-1,4-butanediyl)
OEt OEt OEt
| | |
[EtO-Si-OEt . EtO-Si-(OCH2CH2CH2CH2)n-O-Si-OEt]x
| | |
OEt OEt OEt
MF (C8H20O4Si . (C4H8O)nC12H30O7Si2)x
CA File: Siloxanes and Silicones (silicate-)
7. End Groups for Siloxane SRUs
End groups for siloxane SRUs are not assumed except in the case of nonreactive commercial siloxanes. For such siloxanes, Me3Si- end groups are commonly incorporated to provide stability and are a standard assumption. Hydroxy end groups are used for siloxane SRUs only when so indicated or implied.
8. Siloxane Components in Copolymers
When registrable siloxanes appear as components in copolymers, they are included in the copolymer either as terminated SRUs (homopolymer siloxanes) or, in the case of copolymer siloxanes, as the identified or assumed (hydroxysilanes) monomers.
Example 1: A block siloxane-polyurethane prepared from H(OSiMe2)
nOH toluene diisocyanate, and 1,4-butanediol.
Registry File: 1,4-Butanediol, polymer with
1,3-diisocyanatomethylbenzene and .alpha.-hydro-
.omega.-hydroxypoly[oxy(dimethylsilylene)], block
Me
|
[ HO(CH2)4OH . H-(O-Si-)n-OH . TDI ]
| x
Me
MF ((C9H6N2O2 . C4H10O2 . (C2H6OSi)nH2O)x
CA File: Siloxanes and Silicones
(polyurethane-, block)
Urethane polymers
(siloxane-, block)
---
Example 2: A block siloxane-polyester from Me2SiCl2-Ph2SiCl2
hydrolytic siloxane, 1,4-butanediol, and adipic acid.
Registry File: Hexanedioic acid, polymer with 1,4-butanediol and
dichlorodimethylsilane hydrolytic polymer with
dichlorodiphenylsilane, block
Me Ph
| |
[HO2C(CH2)4CO2H . HO(CH2)4OH . (Cl-Si-Cl . Cl-Si-Cl . H2O)x]x
| |
Me Ph
MF ((C12H10Cl2Si . C2H6Cl2Si . H2O)x . C6H10O4 . C4H10O2)x
CA File: Siloxanes and Silicones
(polyester-, block)
Polyesters
(siloxane-, block)
---
Example 3: A siloxane-polyester from HO(-Me2SiO-)x(-Ph2SiO-)yH,
1,4-butanediol, and adipic acid.
Registry File: Hexanedioic acid, polymer with 1,4-butanediol,
dimethylsilanediol and diphenylsilanediol, block
(Based on assumed monomers for the siloxane component)
Me Ph
| |
[HO2C(CH2)4CO2H . HO(CH2)4OH . HO-Si-OH . HO-Si-OH]x
| |
Me Ph
MF (C12H12O2Si . C6H10O4 . C4H10O2 . C2H8O2Si )x
CA File: Siloxanes and Silicones
(polyester-, block)
Polyesters
(siloxane-, block)
9. Trade Names
Trade names for siloxanes and silsesquioxanes are cross-referred to the SRU when such can be registered. When the SRU is not registrable, cross-references are written to the controlled-term heading SILOXANES AND SILICONES or SILSESQUIOXANES with appropriate substituent descriptions in the text modification.
10. Silicone Rubbers
Silicone rubbers are indexed at the modified controlled-term heading RUBBER, SILICONE. Additional entries are made for the polymer based on actual or assumed (hydroxysilane) monomers and for the SRU whenever possible. No entries are made at the controlled-term heading SILOXANES AND SILICONES for rubbers.
Text modifications at the modified controlled-term heading RUBBER, SILICONE typically contain a description of substituents on the siloxane backbone. Trade names for silicone rubbers are cross-referred to the modified heading RUBBER, SILICONE with substituent information placed in the text modification at that heading.
Example 1: Di-Me silicone rubber
Registry File: Poly[oxy(dimethylsilylene)] [9016-00-6]
Silanediol, dimethyl-, homopolymer [31900-57-9]
(polymer based on assumed monomer)
(The term "rubber" will appear in the text modification
at both RNs in the CA File.)
CA File: Rubber, silicone
(di-Me)
*具体内容及功能特性可能因产品许可协议而异。