Technical Library

Outline

Macromers are relatively high molecular weight species with a single functional polymerizable group which, although used as monomers, have high enough molecular weight or internal monomer units to be considered polymers. A macromer has one end-group which enables it to act as a monomer molecule, contributing only a single monomeric unit to a chain of the final macromolecule. The term macromer is a contraction of the word macromonomer. Copolymerization of macromers with traditional monomers offers a route to polymers that are usually associated with grafting. Macromers provide a mechanism for introducing pendant groups onto a polymer backbone with conditions consistent with radical, condensation, or step-growth polymerization but result in pendant groups that are usually associated with significantly different polymerization conditions and significantly different physical properties than the main polymer chain. Siloxane macromers afford a mechanism for introducing a variety of desirable properties without disrupting the main chain integrity of an organic polymer.

Two general classes of siloxane macromers are available: asymmetric and symmetric. Asymmetric macromers have been the most widely used, but symmetric monomers, which open a path for hyper-branched polymers, are anticipated to have increased commercial utilization. Macromers are primarily defined by the functional group anticipated to be the reactive functionality in a polymerization. Other modifications usually effect a greater degree of compatibility with the proposed bulk polymer. These include modifying or replacing the most widely used siloxane building block, dimethylsiloxane, with other siloxanes, typically trifluoropropylmethylsiloxane.

Monoaminopropyl-Terminated polydimethylsiloxanes are most widely used as intermediates for acrylamide-functional macromers or as terminating groups for polyamides and polyimides.

Monoaminopropyl-Terminated Polydimethylsiloxanes - asymmetric

Product CodeViscosity (cSt)Molecular WeightRefractive IndexDensity
MCR-A118-12800-1,0001.4110.92
MCR-A1218-252,0001.4110.97

Monoacrylamidopropyl-Terminated Polydimethylsiloxane

Product CodeViscosity (cSt)Molecular WeightRefractive IndexDensity
MCR-W1550-701,000-1,5001.4180.96

Monocarbinol-terminated silicones are pigment dispersants and compatibilizers for a variety of resin systems including epoxies, urethanes, and silicones. The action of these materials has been likened to surfactants for non-aqueous systems.

Monocarbinol-Terminated Polydimethylsiloxanes, Hydroxyethoxypropyl-Terminated - asymmetric, CAS: [207308-30-3], TSCA

Product CodeViscosity (cSt)Molecular WeightRefractive IndexDensity
MCR-C1215-201,0001.4090.96
MCR-C1880-905,0001.4050.97
MCR-C2225010,0001.4040.98
Dispersants for particles, including quantum dots, in silicone elastomers. (Tag, P. et al, J. Mater. Chem. C, 2013, 1, 86)

Monocarbinol-Terminated-Functional Polydimethylsiloxanes - symmetric, CAS: [67674-67-3], TSCA

Product CodeViscosity (cSt)Molecular WeightRefractive IndexDensityComments
MCS-C115-15280-3801.4130.905n=0
CAS: [17962-67-3]
MCS-C1335-40550-6501.4461.02n=6-9
CAS: [67674-67-3]

Monodicarbinol-Terminated Polydimethylsiloxanes - asymmetric, CAS: [218131-11-4]

Product CodeViscosity (cSt)Molecular WeightRefractive IndexDensity
MCR-C6150-601,0001.4170.97
MCR-C62100-1255,0001.4090.97
MCR-C63200-25015,0001.4060.97
Diol-terminated silicones improve electrical and release properties of polyurethanes and can be components
in synthetic leather.

Carboxylic acid-terminated silicones form esters. They also behave as surfactants.

Monocarboxydecyl-Terminated Polydimethylsiloxanes - asymmetric

Product CodeViscosity (cSt)Molecular WeightRefractive IndexDensity
MCR-B12201,5001.4150.94

Monofunctional epoxy-terminated silicones have been utilized as modifiers for aliphatic epoxy systems. They have been used as thermal stress reduction additives to epoxies employed in electronic applications. They have also been acrylated to form UV-curable macromers.

Mono (2,3-Epoxy)Propylether-Terminated Polydimethylsiloxanes - asymmetric, CAS:[1108731-31-2]/[127947-26-6], TSCA

Product CodeViscosity (cSt)Molecular WeightRefractive IndexDensity
MCR-E1110-151,0001.4100.96
MCR-E211205,0001.4080.97

Mono (2,3-Epoxy)Propylether-Functional Polydimethylsiloxanes - symmetric

Product CodeViscosity (cSt)Molecular WeightRefractive IndexDensity
MCS-E1545-55800-9001.3981.09

Hydride-functional macromers can be derivatized or reacted with a variety of olefins by hydrosilylation. They are also modifiers for platinum-cure silicone elastomers.

Monohydride-Terminated Polydimethylsiloxanes - asymmetric, CAS:[1038821-58-7], TSCA

Product CodeViscosity (cSt)Molecular WeightRefractive IndexDensity
MCR-H075-8800-9001.4040.96
MCR-H118-12900-1,1001.4070.96
MCR-H2180-1204,500-5,0001.4110.96
MCR-H22150-25010,0001.4110.98

The most widely employed silicone macromers are methacrylate functional. Applications have been reported for hair spray,1 contact lens,2 pigment dispersion,3 and adhesive release.4 The materials copolymerize smoothly with other acrylate and styrenic monomers as indicated by their reactivity ratios.

1. US Pats 5166276, 5480634
2. JP-A-230115/90, US Pat 6,943,203
3. US Pat 6,991,884
4. US Pat 4,728,571

Monomersr1 : r2*
MCR-M11 : methylmethacrylatenm** : 1.60
MCR-M22 : methylmethacrylatenm** : 2.10
MCR-M11 : styrene0.26 : 1.07
MCR-M11 : acrylonitrile5.4 : 0.89
MacromerSolubility (wt%) in DimethylacrylamideSolubility (wt%) in Hydroxyethylmethacrylate
MCR-M1141
MCR-M1182
MCR-M15100 (miscible)2

Monomethacryloxypropyl-Terminated Polydimethylsiloxanes - asymmetric, CAS: [146632-07-7], TSCA

Product CodeViscosity (cSt)Molecular WeightRefractive IndexDensity
MCR-M076-9600-8001.4160.96
MCR-M1110800-1,0001.4110.96
MCR-M1770-805,0001.4060.97
MCR-M22150-20010,0001.4050.97
inhibited with BHT

Monomethacryloxypropyl-Functional Polydimethylsiloxanes - symmetric, CAS: [868684-55-3]/[104780-61-2], TSCA

Product CodeViscosity (cSt)Molecular WeightRefractive IndexDensity
MCS-M117-9800-1,0001.4170.93
inhibited with BHT

Monomethacryloxypropyl-Terminated Polytrifluoropropylmethylsiloxanes - asymmetric

Product CodeViscosity (cSt)Molecular WeightRefractive IndexDensity
MFR-M1550-70800-1,0001.3981.09
inhibited with BHT

Monomethacryloxypropyl-Functional Polytrifluoropropylmethylsiloxanes - symmetric, CAS: [1072456-00-8]

Product CodeViscosity (cSt)Molecular WeightRefractive IndexDensity
MFS-M1540-60800-1,0001.3981.09
inhibited with BHT

Monotriethoxysilylethyl-Terminated Polydimethylsiloxanes - asymmetric

Product CodeViscosity (cSt)Molecular WeightRefractive IndexDensity
MCR-XT1116-24500-1,0001.4120.97

Monovinyl-functional siloxanes are utilized to control modulus and tack in silicone gels, elastomers, and coatings.

Monovinyl-Terminated Polydimethylsiloxanes - asymmetric

Product CodeViscosity (cSt)Molecular WeightRefractive IndexDensity
MCR-V2180-1205,500-6,5001.4030.97
MCR-V25400-60015,000-20,0001.4030.97
MCR-V418,000-12,00055,000-65,0001.4040.98

Monovinyl-Functional Polydimethylsiloxanes - symmetric, TSCA

Product CodeViscosity (cSt)Molecular WeightRefractive IndexDensity
MCS-V21216-241,200-1,4001.4190.97

Macromers with polar terminations can be used as additives into more polar organic resins to add silicone characteristics with reduced likelihood of phase separation.

Monomethacryloxypropyl-Functional Polydimethylsiloxanes, Methoxypropy-Terminated - symmetric

Product CodeViscosity (cSt)Molecular WeightRefractive IndexDensity
MCS-MX118-121,0001.4300.96

Monovinyl-Functional Polydimethylsiloxane, Methoxy(diethyleneoxide)propyl-Terminated - symmetric, CAS:[1586018-77-0]

Product CodeViscosity (cSt)Molecular WeightRefractive IndexDensity
MCS-VX1540-605,0001.4120.96

Monovinyl-Functional Polydimethylsiloxane, Tetrahydrofurfuryloxypropyl-Terminated - symmetric, CAS:[1581252-46-1]

Product CodeViscosity (cSt)Molecular WeightRefractive IndexDensity
MCS-VF1435-452,000-3,0001.4140.97

Silylated macromers provide a route to incorporation of polar monomers into mixtures of non-polar monomers. Subsequent to polymerization, the trimethylsilyl group is removed by hydrolysis.

Monoallyl-Monotrimethylsiloxy-Terminated Poly(Ethylene Oxide) - asymmetric

Product CodeViscosity (cSt)Molecular WeightRefractive IndexDensity
SIA0479.020-255001.4561.04

Monomethacryloxy-Monotrimethylsiloxy-Terminated Poly(Ethylene Oxide) - asymmetric

Product CodeViscosity (cSt)Molecular WeightRefractive IndexDensity
SIM6485.9--400--1.02

Poly(Ethylene Oxide) Monoallyl-, Monoamine-Terminated, Silylated

Product CodeViscosity (cSt)Molecular WeightRefractive IndexDensity
ENEP37124-5400-600----