N-[3-(triethoxysilyl)propyl]ethylenediamine

Phototransformation in air

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

phototransformation in air

Type of information:

(Q)SAR

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Principles of method if other than guideline:

Calculation based on AOPWIN v1.92, Estimation Programs Interface Suite™ for Microsoft® Windows v 4.11. US EPA, United States Environmental Protection Agency, Washington, DC, USA.

GLP compliance:

no

Estimation method (if used):

PHOTOCHEMICAL REACTION WITH OH RADICALS
- Concentration of OH radicals: 0.5E+06 radicals/cm3
- Degradation rate constant: 129.0788 E-12 cm3/molecule-sec
- Temperature for which rate constant was calculated: 25 °C
- Computer programme: AOPWIN v1.92

DT50:

2.9 h

Test condition:

calculation based on a 24 h day

AOP Program (v1.92) Results:

===========================

SMILES : NCCNCCC[Si](O)(O)O

MOL FOR: C5 H16 N2 O3 Si1

MOL WT : 180.28

------------------- SUMMARY (AOP v1.92): HYDROXYL RADICALS (25 deg C) --------

Hydrogen Abstraction      = 34.7288 E-12 cm3/molecule-sec

Reaction with N, S and -OH = 94.3500 E-12 cm3/molecule-sec

Addition to Triple Bonds  =  0.0000 E-12 cm3/molecule-sec

Addition to Olefinic Bonds =  0.0000 E-12 cm3/molecule-sec

Addition to Aromatic Rings =  0.0000 E-12 cm3/molecule-sec

Addition to Fused Rings   =  0.0000 E-12 cm3/molecule-sec

 

  OVERALL OH Rate Constant = 129.0788 E-12 cm3/molecule-sec

  HALF-LIFE =    0.124 Days (24-hr day; 0.5E6 OH/cm3)

  HALF-LIFE =    2.983 Hrs

------------------- SUMMARY (AOP v1.91): OZONE REACTION (25 deg C) -----------

 

              ****** NO OZONE REACTION ESTIMATION ******

              (ONLY Olefins and Acetylenes are Estimated)

 

Experimental Database: NO Structure Matches

Fraction sorbed to airborne particulates (phi):

 0.783 (Junge-Pankow, Mackay avg)

 0.999 (Koa method)

    Note: the sorbed fraction may be resistant to atmospheric oxidation

 

 

 

Reference 2

Endpoint:

phototransformation in air

Type of information:

(Q)SAR

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Principles of method if other than guideline:

Calculation based on AOPWIN v1.92, Estimation Programs Interface Suite™ for Microsoft® Windows v 4.11. US EPA, United States Environmental Protection Agency, Washington, DC, USA.

GLP compliance:

no

Estimation method (if used):

PHOTOCHEMICAL REACTION WITH OH RADICALS
- Concentration of OH radicals: 0.5E+06 radicals/cm3
- Degradation rate constant: 137.2490 E-12 cm3/molecule-sec
- Temperature for which rate constant was calculated: 25 °C
- Computer programme: AOPWIN v1.92

DT50:

2.8 h

Test condition:

calculation based on a 24 h day

AOP Program (v1.92) Results:

===========================

SMILES : NCCNCCC[Si](OCC)(OCC)OCC

MOL FOR: C11 H28 N2 O3 Si1

MOL WT : 264.44

------------------- SUMMARY (AOP v1.92): HYDROXYL RADICALS (25 deg C) --------

Hydrogen Abstraction      = 53.2490 E-12 cm3/molecule-sec

Reaction with N, S and -OH = 84.0000 E-12 cm3/molecule-sec

Addition to Triple Bonds  =  0.0000 E-12 cm3/molecule-sec

Addition to Olefinic Bonds =  0.0000 E-12 cm3/molecule-sec

Addition to Aromatic Rings =  0.0000 E-12 cm3/molecule-sec

Addition to Fused Rings   =  0.0000 E-12 cm3/molecule-sec

 

  OVERALL OH Rate Constant = 137.2490 E-12 cm3/molecule-sec

  HALF-LIFE =    0.117 Days (24-hr day; 0.5E6 OH/cm3)

  HALF-LIFE =    2.806 Hrs

------------------- SUMMARY (AOP v1.91): OZONE REACTION (25 deg C) -----------

 

              ****** NO OZONE REACTION ESTIMATION ******

              (ONLY Olefins and Acetylenes are Estimated)

 

Experimental Database: NO Structure Matches

Fraction sorbed to airborne particulates (phi):

 0.00156 (Junge-Pankow, Mackay avg)

 0.0268 (Koa method)

    Note: the sorbed fraction may be resistant to atmospheric oxidation

 

Conclusions:

Half-life of N-[3-(triethoxysilyl)propyl]ethylenediamine (CAS 5089-72-5) in the air is calculated as 2.8 hours.

Additional information

N-[3-(triethoxysilyl)propyl]ethylenediamine (CAS 5089-72-5) and its hydrolysis product N-[3-(trihydroxysilyl)propyl]ethylenediamine contain no chromophores that would absorb visible or UV radiation, so direct photolysis is not likely to be significant. Indirect photolysis resulting from gas-phase reaction with photochemically-produced hydroxyl radicals may occur.

The SRC AOPWIN program (v1.92) has been used to obtain values of the rate constant kOH for reaction of N-[3-(triethoxysilyl)propyl]ethylenediamine (CAS 5089-72-5) and its hydrolysis product N-[3-(trihydroxysilyl)propyl]ethylenediamine with hydroxyl radicals. This prediction method has not been validated to assess applicability to silanes and silanols, therefore, there is uncertainty associated with the calculated values obtained.

The overall half-life in air under default conditions of hydroxyl radical concentration was calculated using the following expressions:

kdeg_air(d^-1) = k_OH(cm³/molecule. sec) x OH Conc_air(molecules/cm³) x 24 x 3600

DT₅₀(d) = ln 2/ kdeg_air(d^-1)

Where:

kdeg_air= total rate constant for degradation in air

k_OH= rate constant for reaction with hydroxyl radicals

OH Conc_air= concentration of hydroxyl radicals in air = 5 x 10⁵OH molecules/ cm³

DT₅₀= half-life

The results are given in table below:

Table 4.1.2: Predicted photodegradation in air.

Parameter	N-[3-(triethoxysilyl)propyl]ethylenediamine	N-[3-(trihydroxysilyl)propyl]ethylenediamine	Ethanol
kOH(cm3/molecule. sec)	137.2490 E-12	129.0788 E-12	3.6 x10-12
kdegair (d-1)	5.92	5.57	0.2
DT50(days)	0.117 Days (24-hr day; 0.5E6 OH/cm3)	0.124 Days (24-hr day; 0.5E6 OH/cm3)	4.5(24-hr day; 0.5E6 OH/cm3)