Sustainable Soil Surfactants for Turfgrass Management

DATE AUTHOROctober 13, 2010 PAUL T. BIALLY

Sustainable Soil Surfactants for Turfgrass Management

Irrigation Efficiency in Turfgrass Systems

Water use efficiency and conservation are essential

for sustainable turfgrass management.

The slightest water deficits can

impact turf health, appearance, and

performance.

Excessive irrigation can be equally

detrimental leading to increased

erosion, run-off, nutrient leaching,

disease susceptibility, and resource

costs.

Irrigation Efficiency in Turfgrass Systems

Achieved when turf being irrigated uses most of the water applied by irrigation systems.

Dependent on:1. water being applied as uniformly as possible

2. water being applied in proper amounts at appropriate time intervals

source

Irrigation Efficiency Benefits

• Improved appearance• Better playing conditions (golf, sports fields)

• Reduced water use• Reduced runoff and leaching• Reduced agrochemical usage• Reduced pump operation, energy, and

maintenance costs

source

Mechanical Advances Are Essential

Allow growers to control timing, duration, and uniformity of water applied to the plant and soil surface.

Unable to control delivery

of applied water below the

surface and into the root

zone, where many

agronomic and economic

benefits are realized.

The Impact of Impervious Land Cover*

Natural Ground Cover 10-20% Impervious Surface

35-50% Impervious Surface 75-100% Impervious Surface

10% Runoff 20% Runoff

30% Runoff

55% Runoff

*roads, parking lots, sidewalks, roof tops, patios, etc.

Esterified

Water Droplet Interaction with the Land Surface

contact angle <90° 90° or greater

water

water

air

land surfaceland surface

air

infiltration no infiltration

influenced biochemically by oils and waxes from plants, microbes, agrochemical residue, pollutants, etc.

Prior Discoveries

* Intellectual property of Aquatrols Corp (Paulsboro, NJ, USA)

There is an ongoing

need for new

technologies with

superior

performance and

environmental

profiles.

Irrigation Surfactant Development

Organic Chemistry of Esters

Carboxylic acid derivatives in which hydroxyl group

(-OH) is replaced by an alkoxy group (-OR)

R—C—OH + R’—OH R—C—O—R’ + H2O

Esterification:OO

ACID ALCOHOL ESTER

Synthesis of Alkyl Polyglucosides

OO

OOHH

OOHHOOHH

OOHHOOHH HHOO

OOOOHH

OOHHOOHH

OOOOHH

OOHHOOHH

OOHH

OO

OO

-- HH22OO

HH++

nn

nnmm

++

GLUCOSE FATTY

ALCOHOL

ALKYL

POLYGLUCOSIDE

1) Maleic Anhydride

2) Sodium Sulfite

1) Citric Acid

2) Sodium Hydroxide

1) Tartaric Acid

2) Sodium Hydroxide

AlkylpolyglucosideAlkylpolyglucoside

SulfosuccinateSulfosuccinate

OOHH

++

OOOOHH

OOHHOOHH

OOOOHH

OOHHOOHH

OO

OO

nnmm

Alkylpolyglucoside

Synthesis of Alkyl Polyglucoside Esters (AGEs)

AlkylpolyglucosideAlkylpolyglucoside

CitrateCitrate

AlkylpolyglucosideAlkylpolyglucoside

TartrateTartrate

AGEs Retain Favorable APG Properties…

Derived from

natural, renewable

raw materials

Strong biological

performance as

built-in and tank

mix adjuvants

Biodegradable,

not harmful to

the environment

Free from dioxane,

ethylene oxide, and

nitrosamine

precursors

Mild to skin and

non-irritating to

the eyes

AGEs Offer Unique Efficacy

ISAA 2010

ISAA 2007

PATENT PENDING

Hydrophobicity* Effects on Water Penetration

1% 5% 10%

15% 20% 50%

WETTABLE WETTABLE REPELLENT

STRONGLY

REPELLENTIMPERVIOUS IMPERVIOUS

*Dimethyldichlorosilane treatments

Droplet Penetration Effects

WDPT (s)

Treatment 8000mgL-1 2000mgL-1 1000mgL-1 500mgL-1

Citrate Ester 2.0 52.6 68.0 155.0

Tartrate Ester 2.0 61.4 83.3 180.0

Sulfosuccinate Ester 2.8 65.2 100.7 135.0

L61 4.2 110.6 128.3 325.9

31R1 5.5 121.0 284.2 471.8

L62 8.0 152.7 167.9 468.4

25R2 9.8 203.3 394.4 >600

L64 8.0 511.4 >600 >600

APG (C8-10) 3.0 >600 >600 >600

APG (C9-11) 3.0 >600 >600 >600

Top 3 performers in GREEN

Droplet Penetration Effects

0

100

200

300

400

500

600

8000mgL-1 2000mgL-1 1000mgL-1 500mgL-1

Time (s)

Favorable Combinations with

Commonly Used Surfactants

WDPT (s)

Treatment 2000mgL-1

L61 Block Copolymer 305.9

APG (C8-10) 280.9

1:1 APG to L61 72.7

Sulfosuccinate Ester 23.4

1:1 SS to L61 5.0

OTS-treated sand

Effect of Blending Ratio

on Wetting EfficacyWDPT (s)

2000mgL-1

Treatment 3:1 1:1 1:3

Citrate Ester + Block Copolymer 71.8 37.2 330.0

Tartrate Ester + Block Copolymer 51.8 41.6 128

Sulfosuccinate Ester + Block Copolymer 140 57.8 480

OTS-treated sand

GREEN denotes synergies

Mini Disk Infiltrometer (MDI)•Measures hydraulic conductivity and infiltration

rate of the medium it is placed upon.

•Can also be used to measure soil water

repellency index and evaluate wetting agent

efficacy.

Property of Decagon Devices, 2007.

bottom view

Mini Disk Infiltrometer (MDI)

Infiltration = I = C1t + C2√t

Hydraulic Conductivity = k = C1/A

where C1 is the slope of the curve of

cumulative infiltration vs square root of time

and A = 11.65(n0.1-1)exp [2.92(n-1.9)αh0]

(αr0)0.91

related to soil parameters

Property of Decagon Devices, 2007.

Hydrophobicity* Effects on Water Penetration Rate

1% 5% 10%

15% 20% 50%

1.4 mL/s 1.3 mL/s 1.0 mL/s

0.7 mL/s

*Dimethyldichlorosilane treatments

0.0 mL/s 0.0 mL/s

Natural Variations in Infiltration Rate (mL/s)

15ft

15ft

0.23 0.13

0.270.33

0.13

0.23

0.30 0.400.33

Infiltration Rate (mL/s) following 1.0” Rain Event

Mean

Infiltration Rate

Time after rain mL/s mL/min

30 minutes 0.47 28

24 hours 0.30 18

48 hours 0.20 12

72 hours 0.10 6

96 hours 0.10 6

Infiltration Rate (mL/s) with Surfactant Treatment

Mean

Infiltration Rate

Treatment (500mgL-1

) mL/s mL/min

Control (96 hr) 0.10 6

C8-10 APG 0.10 6

L62 0.13 8

Citrate Ester 0.15 9

Tartrate Ester 0.15 9

Sulfosuccinate ester 0.17 10

1:1 EC to L62 0.23 14

Conclusions and Future Outlook

Performance advantages are apparent in the esterification of nonionic APGs.

APG esters can be highly effective at delivering irrigation water and agrochemicals to the root zone of turfgrass. Synergies are apparent with commonly used surfactants.

Patent pending. Research is underway to further investigate these properties.