Overcoming Challenges in Biodegradable Plastics for Manufacturing Plastic Parts

Introduction

In 2022, global production of biodegradable plastics reached 1.3 million metric tons, accounting for nearly 55% of all bioplastics produced. By 2027, this figure is projected to exceed 3.5 million metric tons, driven by increasing adoption in packaging, consumer goods, automotive, and medical applications. (Source: European Bioplastics, 2023).

Overcoming Challenges in Biodegradable Plastics for Manufacturing Plastic Parts

The increasing demand for sustainable alternatives in plastic parts manufacturing is driven by environmental concerns, government regulations, and the need to reduce dependence on petroleum-based plastics.

Industries such as packaging, automotive, medical, and consumer goods are rapidly adopting biodegradable plastics for plastic parts manufacturing to meet sustainability goals. However, the shift to biodegradable materials presents significant challenges in plastic injection molding, requiring advanced processing techniques and precise control over material properties.

As a plastic parts manufacturer in India, Vidhata Plastics has developed specialized expertise in processing biodegradable plastics using state-of-the-art injection molding technology. This blog explores the types of biodegradable plastics used, the step-by-step manufacturing process, the challenges faced, and the innovative solutions Vidhata Plastics employs to produce high-quality plastic parts.

Types of Biodegradable Plastics Used in Plastic Parts Manufacturing

Not all biodegradable plastics are created equal. Their performance, processing requirements, and degradation behavior vary based on composition. Vidhata Plastics carefully selects materials based on mechanical properties, biodegradability, and compatibility with plastic injection molding processes.

1. Polylactic Acid (PLA)

Source: Derived from corn starch or sugarcane.
Properties: High tensile strength, excellent clarity, and good processability in injection molding.
Applications: Medical implants, packaging, disposable cutlery, and electronic casings.
Challenges: Low heat resistance, brittle nature, and sensitivity to hydrolysis.

2. Polyhydroxyalkanoates (PHA)

Source: Bacteria-based fermentation of plant-derived sugars and oils.
Properties: High biodegradability in marine and soil environments, good flexibility, and thermal stability.
Applications: Biodegradable packaging, medical sutures, and agricultural films.
Challenges: Expensive production process, requires precise temperature control during molding.

3. Starch-Based Plastics

Source: Blend of natural starch with biodegradable polyesters such as PBAT (polybutylene adipate terephthalate).
Properties: High biodegradability, low cost, but weaker mechanical properties.
Applications: Food packaging, agricultural mulching films, and disposable consumer goods.
Challenges: Absorbs moisture quickly, leading to dimensional instability.

4. Polybutylene Succinate (PBS)

Source: Synthetic biodegradable polyester made from succinic acid and 1,4-butanediol.
Properties: Similar to polypropylene (PP), good impact resistance, excellent flexibility.
Applications: Automotive parts, electronic housings, and medical devices.
Challenges: Requires tight process control to avoid degradation during molding.

Manufacturing Process of Plastic Parts with Biodegradable Plastics at Vidhata Plastics

Vidhata Plastics, a leading plastic injection mold manufacturer in India, follows a scientifically controlled process to manufacture plastic parts with biodegradable plastics for plastic parts manufacturing.

Step 1: Material Selection and Preprocessing

Before molding, biodegradable plastics are tested and conditioned to maintain optimal performance:

Moisture Control: PLA and PHA are highly sensitive to moisture. Dehumidifying dryers are used to reduce moisture levels to below 0.02% to prevent hydrolytic degradation.
Melt Flow Index (MFI) Analysis: This ensures that the polymer's flow properties are compatible with the molding process.
Material Blending: In some cases, biodegradable fillers or natural fibers (e.g., cellulose, bamboo fiber) are added to enhance strength.

Step 2: Mold Design & Tooling Optimization

As a mould manufacturer in India, Vidhata Plastics designs injection molds specifically for biodegradable materials:

Low Shear Design: Biodegradable plastics degrade under high shear forces. The mold runner and gate systems are optimized to ensure smooth polymer flow.
Thermal Regulation: Uniform mold temperature control prevents uneven cooling and warping of parts.
Venting Strategy: Biodegradable plastics release gases during molding, requiring specialized venting systems to prevent burn marks.

Step 3: Injection Molding Process

The actual molding process involves precision engineering to ensure defect-free parts:

Barrel Temperature Management: PLA requires 160–190°C, while PHA and PBS need 180–220°C to prevent degradation.
Screw Speed Control: Optimized to prevent excessive shear stress, ensuring material integrity.
Injection Pressure: Typically lower than traditional plastics to prevent degradation and maintain part dimensions.
Cycle Time Optimization: Some biodegradable plastics, such as PLA, require longer cooling times to prevent warping.

Step 4: Post-Processing & Quality Control

After molding, plastic parts manufacturing with biodegradable plastics undergo a series of finishing and inspection steps:

Annealing for Dimensional Stability: PLA-based parts are heat-treated to reduce residual stress.
Surface Treatment: Techniques like plasma treatment improve adhesion for coatings and paints.
Biodegradability Testing: Parts undergo accelerated compostability tests to ensure compliance with environmental standards.

Challenges in Biodegradable Plastic Parts Manufacturing & Vidhata Plastics' Advanced Engineering Solutions

1. Thermal Sensitivity & Precision Processing

Challenge: Biodegradable plastics like PLA and PHA have lower thermal stability, degrading at 200–250°C, unlike conventional polymers like PP (~260–280°C). This leads to molecular weight reduction and poor mechanical integrity.
Solution: Vidhata Plastics employs differential scanning calorimetry (DSC) and rheological profiling to optimize processing temperatures. Servo-driven injection molding machines with adaptive heat zone regulation prevent localized overheating, ensuring precise thermal control for material integrity.

2. Moisture Absorption & Hydrolytic Degradation

Challenge: PLA, PBS, and starch-based plastics absorb moisture, leading to hydrolysis-driven polymer chain scission, reducing tensile strength and fracture resistance.
Solution: Vidhata Plastics uses a two-stage dehumidification system (desiccant drying + vacuum-assisted moisture removal) to maintain <0.02% moisture content. Sealed nitrogen storage and inline moisture analyzers ensure stability before processing.

3. Mechanical Strength Limitations & Reinforcement

Challenge: Biodegradable plastics exhibit low impact resistance and tensile modulus due to lower crystallinity, limiting structural performance in demanding applications.

Solution: Reinforcement strategies include:

Micro- and nano-cellulose fibers for improved tensile strength.
Graphene/nanoclay composites for enhanced thermomechanical properties.
PLA-PHA polymer blending to balance stiffness and ductility. Dynamic shear mixing ensures uniform dispersion, preventing agglomeration.

4. Narrow Processing Window & Real-Time Monitoring

Challenge: Biodegradable plastics degrade rapidly if processing temperature or shear stress exceeds threshold limits.
Solution: Vidhata Plastics integrates real-time viscometry, infrared spectroscopy, and low-shear screw designs to prevent degradation. Servo-hydraulic injection profiling optimizes flow while variable backpressure control ensures uniform melt distribution.

5. High Material Costs & Cost-Effective Processing

Challenge: PLA ($2.5–$4/kg), PHA ($4–$6/kg), and PBS ($3–$5/kg) cost significantly more than PP ($1.2/kg).

Solution:

Thin-wall injection molding (≤0.4 mm) reduces material use.
Mold flow simulation (Moldex3D) optimizes polymer distribution.
Multi-cavity molds increase production efficiency.
Post-industrial regrind recycling minimizes material waste.

By leveraging advanced processing techniques and material science innovations, Vidhata Plastics ensures high-performance, cost-efficient manufacturing of biodegradable plastic parts.

Benefits of Biodegradable Plastics in Injection Molding

Despite processing challenges, biodegradable plastics for plastic parts manufacturing offer significant advantages:

1. Environmental Sustainability

Reduced Carbon Footprint: 60–80% lower CO₂ emissions compared to petroleum-based plastics.
Less Plastic Waste: Fully compostable, reducing landfill dependency.

2. Compliance with Global Regulations

Meets European EN 13432, US ASTM D6400, and Indian CPCB biodegradable standards.

3. Market Demand & Brand Value

Consumer preference for eco-friendly products is increasing, boosting demand for plastic parts manufacturing with biodegradable plastics.

4. Versatility Across Industries

Used in medical devices, food packaging, automotive components, and agricultural applications.

Conclusion:

As a top plastic injection mold manufacturer in India, Vidhata Plastics has successfully integrated biodegradable plastics for plastic parts manufacturing through advanced engineering and precision processing. By overcoming the challenges of biodegradable plastics, Vidhata Plastics ensures high-quality, durable, and sustainable plastic parts for various industries.

If your business is looking for sustainable plastic parts manufacturing with biodegradable plastics, Vidhata Plastics is your ideal partner. Contact us today to explore how our expertise in plastic injection molding can support your sustainability goals.

Visit Our Website: https://www.vidhata.co.in/

Email Id: info@vidhata.co.in

WhatsApp No. : +919550665666