## 3 Results  
### Physicochemical Properties  
The biochemical and mineral compositions ofarches and other natural polymer resources from various plants play a key role in the development of biodegradable multi films. Monitoring the composition and properties of raw materials used for the production and modification of polymers is essential to maintaining their functional characteristics and ensuring the required product quality at every stage of the process.  
The primary physicochemical properties ofarches obtained from natural raw materials, such as potatoes, wheat, corn, peas, rice, and cassava, are summarized in Table 2.  
Numerous studies have confirmed the significant role of macronutrients and trace elements in the technological and consumer properties of polymers used for manufacturing coating layers [33]. The deficiency of certain elements can negatively affect the strength and flexibility of the resulting materials. Therefore, it is crucial to pay attention to preserving these elements, particularly through recycling. The analysis of mineral composition in various starches used in this study (Table 3) indicates that cassava starch has the highest magnesium content at 43.07 mg/100 g.  
As shown in Table 3, starch from different sources was analyzed to identify the best options for producing biodegradable soil protection films. Potato starch from Northern Kazakhstan, with its high calcium content (30 mg/100 g), enhances plasticity and strength during modification, while its crystallinity provides low-temperature resistance, making it ideal for cold climates [30,34]. Acetylation and oxidation improve its water resistance, making it suitable for high-humidity regions. Cassava starch, with high magnesium content and moderate crystallinity, ensures excellent mechanical performance and elasticity,  
\begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Starch** & **Amylose** & **Amylopectin** & **Water Content** & **Mineral Content** \\ \hline Potato & 20–30 & 70–80 & 12–14 & 0.2–0.3 \\ Wheat & 25–28 & 72–75 & 11–13 & 0.3–0.4 \\ Corn & 24–28 & 72–76 & 10–12 & 0.1–0.2 \\ Pea & 30–35 & 65–70 & 11–13 & 0.2–0.3 \\ Rice & 18–20 & 80–82 & 12–14 & 0.1–0.2 \\ Cassava & 17–24 & 76–83 & 10–12 & 0.1–0.2 \\ \hline \hline \end{tabular}
\end{table}
Table 2: Chemical properties of natural starches %.  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Mineral** & **Cassava** & **Potato Starch** & **Wheat Starch** & **Corn Starch** & **Pea Starch** & **Rice Starch** \\ \hline Zn & 0.48 \(\pm\) 0.04 & 2.6 \(\pm\) 0.08 & 2.63 \(\pm\) 1.66 & 1.3 \(\pm\) 0.06 & 2.3 \(\pm\) 0.09 & 1.0 \(\pm\) 0.16 \\ Mg & 4307 \(\pm\) 39 & 2107 \(\pm\) 44 & 1390 \(\pm\) 99 & 867 \(\pm\) 42.4 & 1757 \(\pm\) 26 & 722.5 \(\pm\) 52.1 \\ Fe & 12.6 \(\pm\) 0.2 & 16.5 \(\pm\) 0.4 & 2.65 \(\pm\) 2.0 & 5.5 \(\pm\) 0.08 & 22.8 \(\pm\) 1.1 & 4.6 \(\pm\) 0.18 \\ Ca & 25.9 \(\pm\) 2.2 & 300 \(\pm\) 5.3 & 299.8 \(\pm\) 8.7 & 210.6 \(\pm\) 3.1 & 250 \(\pm\) 3.3 & 160.6 \(\pm\) 1.1 \\ Se & 12.1 \(\pm\) 0.6 & 3.3 \(\pm\) 0.06 & - & 1.2 \(\pm\) 0.03 & 2.75 \(\pm\) 0.16 & 1.0 \(\pm\) 0.5 \\ \hline \hline \end{tabular}
\end{table}
Table 3: The mineral composition of various types of native starches mg/kg.  
making it ideal for agricultural films that retain moisture and provide protection. Crosslinking and oxidation further enhance its flexibility and crack resistance, supporting natural biodegradability. Corn starch from the Kostanay and Shymkent regions, characterized by high crystallinity, forms strong biodegradable films, and its swelling capacity aids in creating dense coatings after gelatinization [35]. Crosslinking and acetylation improve its strength while maintaining biodegradability, making it suitable for long-term soil coverage. Among these, cassava starch and corn starch exhibit the greatest potential, with cassava offering flexibility and corn providing strength. Modifications through crosslinking and oxidation ensure mechanical durability and effective biodegradation, optimizing the quality and efficiency of biodegradable films [36].