When it comes to the efficacy of a formulation, there are many influencing factors, such as the quality of ingredients, agents, processing technology, formulation form, and crystal structure.
Examining these factors is important for understanding why different manufacturers produce products with varying effects. To address this issue, we’ll use Pyraclostrobin as an example to investigate the content and purity levels that influence the effects of formulations.
What is Pyraclostrobin?
Pyraclostrobin is a carbamate ester that is the methyl ester of [2-({[1-(4-chlorophenyl)-1H-pyrazol-3-yl]oxy}methyl)phenyl] methoxy carbamic acid.
A fungicide used to control major plant pathogens including Septoria tritici, Puccinia spp., and Pyrenophora teres. It is an effective and widely-used carbamate ester fungicide with characteristics that have made it popular among users.
These include a wide sterilization spectrum, high efficiency, safety, health care benefits, and yield enhancement capabilities. It has developed into the third global leading fungicide and is commonly used on cash crops as well as food crops throughout China.
As the demand for this versatile fungicide grows rapidly in the country, Pyraclostrobin continues to be a go-to solution for many farmers worldwide.
What is Crystal Structure?
The arrangement of atoms in a crystal, known as “crystal structure,” is the three-dimensional ordering of atoms in a material. Every material has its own unique crystal structure.
During crystallization, the chemical substances that are dissolved can be affected by different factors, resulting in altered bonding modes between molecules/atoms and thus different arrangements of them in lattice space – ultimately forming various crystal types.
It’s important to note that even products with the same name will have significant differences in properties such as solubility, melting point, dissolution rate, etc. Based on their respective crystal structures – especially for insoluble products which greatly depend on this factor for efficiency.
What will affect the effect of pyraclostrobin formulation?
Content
The content and purity of the active product have the greatest influence on the effect of the formulation. At present, the content of Pyraclostrobin on the market is mostly about 98%, with little difference in content.
Moreover, when processing the formulation, the dosage is converted according to 100, so the current content of Pyraclostrobin has little influence on the effect of the formulation.
Purity
The influence of the purity of the original product on the formulation should not be ignored. It is well known that the products of organic chemical reactions are often multi-component, especially mixtures of isomers.
One of the difficulties in the production of organic chemical pesticides is whether the most active ingredient can be extracted from complex compounds in a higher proportion, that is, to improve the purity of the original product, which is also directly related to the effect of the use of the formulation.
Impurity
The impurity of the active product with different content will be different, which will be related to the use safety of the formulation. The Impurity mostly depends on the different manufacturing processes.
Crystal structure
According to BASF’s patent on Pyraclostrobin crystal form filed on June 19, 2006: Pyraclostrobin is a white or light beige tasteless crystal, easily soluble in acetone, ethyl acetate, toluene, dichloromethane, cyclohexanone, acetonitrile, soluble in methanol, ethanol, isopropyl alcohol, n-butanol, n-octanol, and other organic solvents, slightly soluble in n-heptane, insoluble in water (1.9mg/L, 20℃).
The Chinese Patent publication number CN101203136B also discloses four crystal structures of Pyraclostrobin: crystal type I, crystal type II, crystal type III, and crystal type IV, among which crystal type IV is the most stable solid form.
The effect of crystal structure on the effect of Pyraclostrobin is first because the original product of Pyraclostrobin is solid, and only solid is involved in the difference of crystal structure.
Secondly, the influence of different crystal types on the bioavailability of Pyraclostrobin was mainly reflected in the dissolution rate of active ingredients. Once Pyraclostrobin is completely dissolved, the difference in crystal pattern is eliminated.
When producing suspension form, grinding resistance, temperature requirements, and processing difficulty for different crystal structures Pyraclostrobin is different.
Once Pyraclostrobin was dissolved, such as in emulsion or other fully dissolved formulations, the effect of Pyraclostrobin crystalline form on the formulation is no longer present.
Therefore, only when Pyraclostrobin is used to process suspension agent, the purity of Pyraclostrobin is involved, that is, the crystal structure problem.
Processing technology
The influence of crystal structure on the effect of Pyraclostrobin is also reflected in the difficulty of processing. Because the hardness and melting points of different crystalline agents are different, the resistance produced in the grinding process is also different.
The development of different crystal types of Pyraclostrobin is accomplished through various methods. Crystal type I, manufactured by melting and slow cooling, has a melting point range between 55-56 degrees.
Crystal type II is obtained through the crystallization of Pyraclostrobin dissolved in an organic solvent or mixed solvent. Its melting point range rests at 57-58 degrees.
Meanwhile, Crystal Type III comes from the crystallization of Pyraclostrobin melts at room temperature and presents an even higher melting point range at 59-60 degrees.
Lastly, Crystal Type IV develops from the crystallization process induced by Pyraclostrobin dissolved in either organic or mixed solvent with an optimal temperature targetted between 65-67 degrees and a comprehensive melting point range stretching from 62-72 degrees.
Therefore, in the processing of Pyraclostrobin formulation, the selection of different crystal types of the original product, the effect between them will appear great difference. That’s why BASF filed for a crystal patent 11 years after it filed for a compound patent.
How to ensure technical quality in Pyraclostrobin formulation?
If you want to guarantee the quality of your products, it’s important to choose good manufacturers. Unfortunately, there are some companies that cut corners by illegally producing Pyraclostrobin at low prices without following quality standards.
We recommend looking for a manufacturer with proven formulations, such as Heben – which offers Dimethomorph 12%+ Pyraclostrobin 6.7% WG, Difenoconazole 20% + Pyraclostrobin 10% SC, and more!
Heben is the perfect solution for all your agrochemical needs – so why not give us a call today at 86 (0)577 55882935 or email us at info@hb-p.com to request free samples?