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Q. Liu et al.
flash point, low toxicity, and low volatility, but also to require sufficient viscosity
of the dispersion medium. At present, the relevant research and experience are rare,
thus the suitable oil base can only be selected as a medium based on the properties
of agrochemical varieties and preparations.
Oil base screening is important for an oil suspension preparation. Generally, oils
bases that were widely used include vegetable oils (such as soybean oil, corn oil,
rapeseed oil, cottonseed oil, castor oil, coconut oil, palm oil, turpentine oil, vegetable
oil concentrate, sunflower oil, etc.), vegetable oil esters (rapeseed oil methyl ester,
soybean oil methyl palm oil methyl ester, etc.), and mineral oils (paraffin, methyl
naphthalene advanced aliphatic oil, white oil, etc.), pine fat fatty acid ester, terpinebutyl ester, coconut oil heptyl ester, triglyceride, and its mixed solvent. Among
them, the methylated vegetable oils (methyl oleates) with low viscosity are favored
by various agrochemical research institutions because of their significant efficacy,
low cost, non-toxic, and environmental-friendly characteristics.
Chou et al. [22] prepared 20% oil suspension of fenaminstrobin and tebuconazole
using methyl soybean oil as an oil base. It was proved in indoor tests that the product
has advantages in keeping biological activity. It also has excellent rainwater erosion
resistance and spreading performance. Liu [23] successfully obtained a 5% oil suspension of bacillus subtilis using vegetable oil. In the preparation of 15% oil miscible
flowable concentrate (OF), Liang et al. [24] compared methyl oleate, soybean oil and
its mixture, which had poor solubility to chlorantraniliprole-emamectin benzoate as
a dispersion medium, which had no adverse effect on the thermal stability of the
active ingredients. The methyl oleate was selected as the oil base according to the
parameters of fluidity, emulsifying dispersion, and suspension. Li et al. [25] used
soybean oil to prepare 25% oxadiargyl oil miscible flowable concentrate. Zhao [26]
prepared 20% thiamethoxam oil flowable concentrate using fatty acid methyl ester.
Among the products of oil suspensions, the most widely prepared and used is the
nicosulfuron, and researchers also used different oil bases to prepare nicosulfuron
series oil suspensions. The 4% oil flowable concentrate in the water of nicosulfuron
was prepared using methyl oleate as an oil base, and its dispersion in water was studied
[27]. Yang [28] used the engine oil as the dispersing medium in the preparation of
6% nicosulfuron oil flowable concentrate. And blending soybean oil and dioctyl
phthalate with a volume ratio of 6:1 as the dispersion medium when preparing at 4%
suspension of nicosulfuron was studied. Liu [29] chose biodiesel as the dispersing
medium and also prepared a 4% suspension with superior performance.
9.2.3 Applications of Oils in Spray Auxiliaries
The spray auxiliaries are agrochemical auxiliaries which are directly added to the
spray tank or the agrochemical box before the mixture is sprayed, and they can
improve the physicochemical properties of the liquid agrochemical after being uniformly mixed. They are also generally called bucket additives. Oil-based additives
are an important type of spray auxiliaries. Oil-based spray auxiliaries are classified
Q. Liu et al.
flash point, low toxicity, and low volatility, but also to require sufficient viscosity
of the dispersion medium. At present, the relevant research and experience are rare,
thus the suitable oil base can only be selected as a medium based on the properties
of agrochemical varieties and preparations.
Oil base screening is important for an oil suspension preparation. Generally, oils
bases that were widely used include vegetable oils (such as soybean oil, corn oil,
rapeseed oil, cottonseed oil, castor oil, coconut oil, palm oil, turpentine oil, vegetable
oil concentrate, sunflower oil, etc.), vegetable oil esters (rapeseed oil methyl ester,
soybean oil methyl palm oil methyl ester, etc.), and mineral oils (paraffin, methyl
naphthalene advanced aliphatic oil, white oil, etc.), pine fat fatty acid ester, terpinebutyl ester, coconut oil heptyl ester, triglyceride, and its mixed solvent. Among
them, the methylated vegetable oils (methyl oleates) with low viscosity are favored
by various agrochemical research institutions because of their significant efficacy,
low cost, non-toxic, and environmental-friendly characteristics.
Chou et al. [22] prepared 20% oil suspension of fenaminstrobin and tebuconazole
using methyl soybean oil as an oil base. It was proved in indoor tests that the product
has advantages in keeping biological activity. It also has excellent rainwater erosion
resistance and spreading performance. Liu [23] successfully obtained a 5% oil suspension of bacillus subtilis using vegetable oil. In the preparation of 15% oil miscible
flowable concentrate (OF), Liang et al. [24] compared methyl oleate, soybean oil and
its mixture, which had poor solubility to chlorantraniliprole-emamectin benzoate as
a dispersion medium, which had no adverse effect on the thermal stability of the
active ingredients. The methyl oleate was selected as the oil base according to the
parameters of fluidity, emulsifying dispersion, and suspension. Li et al. [25] used
soybean oil to prepare 25% oxadiargyl oil miscible flowable concentrate. Zhao [26]
prepared 20% thiamethoxam oil flowable concentrate using fatty acid methyl ester.
Among the products of oil suspensions, the most widely prepared and used is the
nicosulfuron, and researchers also used different oil bases to prepare nicosulfuron
series oil suspensions. The 4% oil flowable concentrate in the water of nicosulfuron
was prepared using methyl oleate as an oil base, and its dispersion in water was studied
[27]. Yang [28] used the engine oil as the dispersing medium in the preparation of
6% nicosulfuron oil flowable concentrate. And blending soybean oil and dioctyl
phthalate with a volume ratio of 6:1 as the dispersion medium when preparing at 4%
suspension of nicosulfuron was studied. Liu [29] chose biodiesel as the dispersing
medium and also prepared a 4% suspension with superior performance.
9.2.3 Applications of Oils in Spray Auxiliaries
The spray auxiliaries are agrochemical auxiliaries which are directly added to the
spray tank or the agrochemical box before the mixture is sprayed, and they can
improve the physicochemical properties of the liquid agrochemical after being uniformly mixed. They are also generally called bucket additives. Oil-based additives
are an important type of spray auxiliaries. Oil-based spray auxiliaries are classified