Field revolution: biodegradable mulch film ushers in a breakthrough

        2024 A field trial of PLA/PBAT composite mulch film conducted by the Ministry of Agriculture and Rural Development (MARD) in six major agricultural production areas, including Shandong and Xinjiang, showed that the average degradation cycle of the new generation of mulch film has been shortened to 120 days (traditional PE mulch film takes 200-300 years), which fully matches the growth cycle of crops. The field test covered five major crops and accumulated more than 1,500 sets of monitoring data, providing key support for the commercial application of biodegradable films.

Core data: measured results from three main production areas

1. Timeline of degradation progress

Time point Appearance change Mechanical retention Microbial activity

30 days Longitudinal cracks appeared 78% 3.2×10⁶ CFU/g

60 days Pore size enlarged to 2-3cm 45% 8.7×10⁶ CFU/g

90 days Reticulated fragments 12% 1.2×10⁷ CFU/g

120 days Invisible to the naked eye – 2.3×10⁷ CFU/g

2. Comparison of crop performance

Indicators PLA/PBAT mulch PE mulch Bare ground cultivation

Soil temperature +2.3°C +3.1°C –

Moisture retention Effect Water content 22.3% 23.1% 18.7%

Yield impact +11.2% +12.5% Baseline value

Technology Analysis: Four innovations to ensure degradation efficiency

1. Material ratio optimization

PLA:PBAT=55:45 (optimal balance)

Add 5% nano TiO₂ (photothermal synergistic triggering of degradation)

2. Microporous structure design

Laser perforation density: 28-32 holes/㎡

Pore size gradient: from 50μm to 2mm

3. Soil microorganisms activation

Built-in starch-based microbial nutrient package

Degradation 300% increase in initial colony size

4. Thickness control

0.008mm±0.001mm (conventional PE film 0.012mm)

Longitudinal tensile strength remains 18MPa.

Economic Benefit Analysis (Take cotton planting as an example)

Cost Comparison (mu/season)

Item PLA/PBAT Mulch PE Mulch Difference

Mulch Cost ￥180 ￥70 + ￥110

Recycling Labor – ￥40 – ￥40

Soil Remediation – ￥60 – ￥60

Total ￥180 ￥170 + ￥10

*Note: The actual income after taking into account the biodegradable mulch subsidy of ￥100/mu in 2024*.

Practical Guide for Farmers

1. Notes on Film Laying

Optimal Ground Temperature: 12-15℃ (to avoid low-temperature brittle cracking)

Tension Control: 20% less than PE film

Mulching Thickness: ≥5cm (to prevent wind breakage)

2. List of crop suitability

Recommended crops Applicability Progress in replacing PE

Potato ★★★★★ 35% replaced

Cotton ★★★★☆ 22% replaced

Peanut ★★★★☆☆ Trial phase

Solutions to industry pain points

1. Insufficient initial strength

Countermeasure: choose modified materials containing chain extender (e.g. ADR-4370)

Cost: Increase ￥0.8/㎡

2. Degradation out of sync

Countermeasure: choose formulations according to cumulative temperature (e.g. use fast degradation type for the area with cumulative temperature of ＞10℃ and ￥2000℃)

Tool: Scanning code to view the prediction model of degradation

3. Price sensitivity

Strategy: Apply for the subsidy of the Ministry of Agriculture and Rural Affairs for “Green Agricultural Materials” (2024 budget of RMB 100 million) The budget for 2024 is 500 million RMB)

Policy Dividend Inventory

Central financial subsidies: up to ￥ 1500 / ton (subject to GB / T35795 certification)

Local support:

1.Xinjiang: additional subsidies per mu ￥ 50

2. Shandong: exemption from environmental taxes

3. Export incentives: the EU market can apply for carbon tariff credit vouchers

2025 Market Forecast

1. Capacity explosion: PLA / PBAT film special material capacity of more than 500,000 tons under construction

2. Price decline: expected to fall to ¥ 12-15 / square meter (current price of ¥ 18-20)

3. Technology iteration: light – biological biodegradable film will enter the field test