HiSiaddi is an innovative foreign trade service provider driven by both technology transformation and foreign trade operations, with a "1+2+3+4=1" service system and access to original factory polylactic acid pellet supplies from multiple well-known brands.
As a technology-focused foreign trader, HiSiaddi has repeatedly proposed PLA formula optimization plans and application improvement suggestions through factory technological cooperation and accurate market insight. Below is a consulting case regarding PLA pellet formula optimization.
For inquiries about formula optimization consulting services, please contact HiSiaddi customer service.
HiSiaddi resolved full-chain technical defects covering formula flaws, pelletizing processes, and end-user processing.
The cooperating party, Sweden EcoPack AB, is located in an eco-industrial park in Gothenburg, Sweden, and stands as a leading Nordic manufacturer of premium fresh food and organic food packaging. Its products supply ICA supermarkets, eco-friendly packaging lines for H&M, and local Nordic organic supermarket chains. The three core product lines are ultra-thin fresh food blown film bags, microwaveable biodegradable meal containers, and cold-fill beverage injection molding cups. All products comply with EU standards including EN 13432 compostability, EU 10/2011 food contact materials, and REACH-SVHC control requirements, with stable annual PLA raw material procurement volume of 310 tons.
Prior to cooperation, the enterprise sourced modified PLA pellets exclusively from NatureWorks (USA) and TotalEnergies Corbion. However, raw material prices rose by 32% in recent years, ocean shipping lead times extended to 102 days, and overseas original manufacturers imposed a minimum customized grade order quantity of 60 tons, resulting in high costs for small-batch new product iterations. In 2025, the enterprise officially launched a domestic Chinese PLA alternative procurement project.
The client independently selected two large-scale domestic PLA modification factories and placed an initial 65-ton modified PLA order covering two mainstream grades: dedicated film blowing PLA and heat-resistant injection molding PLA for beverage cups. After production and ocean shipment to the client’s Swedish factory, mass production failures occurred immediately upon startup of fully automatic film blowing and high-speed injection molding lines: ultra-thin films frequently tore during high-speed traction, beverage injection cups deformed and collapsed under microwave heating, and finished products cracked when bent during low-temperature storage. The overall yield rate plummeted from 98.2% (using imported raw materials) to 49.7%, forcing intermittent shutdowns of automated production lines. The client faced delayed delivery penalties for contracted packaging orders to ICA supermarkets, with semi-finished product scrap losses totaling 36,000 EUR.
The two domestic suppliers could only slightly adjust auxiliary agent ratios based on their fixed mass-production formulas. Their R&D resources prioritized low-cost generic domestic packaging clients, preventing root-cause remediation from resin substrates, formula systems, and twin-screw pelletizing processes. Upon referral by the Nordic Bioplastics Industry Association, Sweden EcoPack formally appointed Shanghai HiSiaddi as a third-party technical foreign trade service provider. Our team of polymer modification engineers conducted on-site sampling testing and full-traceability analysis of failure triggers, systematically resolving all technical pain points across four modules: raw material selection, formula reconstruction, twin-screw pelletizing technical renovation, and client-side processing parameter adjustment. Production resumed smoothly after rectification, followed by a long-term annual procurement cooperation framework.
Product Information: Modified PLA pellets, HS Code 3913900000, packed in 25kg kraft paper bags lined with aluminum film for moisture-proof export packaging.
To control costs, domestic factories uniformly adopted low optical purity general homopolymer PLA chips for both grades, with low L-lactide (PLLA) content and no D-lactide (PDLA) blending for stereocomplex modification. The raw material’s inherent heat distortion temperature stood at only 59°C, far below the 85°C microwave standard required for heat-resistant beverage cups. The broad molecular weight distribution and residual monomer content of 315 ppm led to small molecule volatilization during high-temperature melting, causing internal hidden bubbles in injection molded products and severely reducing melt strength – the fundamental cause of frequent rupture during ultra-thin film blowing.
1. Film blowing PLA formula: Factories adopted cheap industrial-grade PBAT and ordinary petrochemical plasticizers, with unbalanced PLA/PBAT blending ratios not tailored to the 22μm ultra-thin film toughness specification. Uneven dispersion of auxiliary agents resulted in insufficient film toughness and instant tearing under high-speed traction tension. Lubricants used were not listed on EU food approval inventories, leading to excessive auxiliary agent migration upon grease contact and failure to pass Swedish food import inspection.
2. Heat-resistant injection molding PLA formula: Only generic talc was added for reinforcement without food-grade bio-based nucleating agents or high-temperature antioxidant systems, and no stereocomplex modification components were incorporated. Finished products suffered dual underperformance in heat resistance and low-temperature impact resistance, developing full-thickness cracks when bent at -18°C cold storage and softening/collapsing rapidly under microwave heating.
The two domestic factories shared universal extrusion lines for multiple product grades without dedicated isolated production lines, causing cross-contamination between different material grades. The full general PLA processing temperature profile was retained for melting zones, triggering thermal degradation of PLA at elevated temperatures. Insufficient vacuum devolatilization failed to fully remove residual monomers and moisture within raw materials, resulting in pellet moisture content exceeding the standard by 0.08% – water vapor vaporized during client-side melting and formed product defects. Bulk powder fillers were added all at once, leading to agglomeration and uneven distribution of internal components within modified pellets.
Swedish production technicians long calibrated equipment based on the crystallization rate and melt flow index of imported NatureWorks PLA. The melting range, crystallization speed, and melt viscosity of domestic modified PLA differed significantly from imported materials, rendering existing film blowing traction speeds, injection barrel temperature settings, and mold cooling durations incompatible with the new raw materials. This further amplified defects including cracking, thermal deformation, and film rupture, leaving the client unable to resolve production issues despite repeated minor parameter adjustments and forcing line shutdowns.
HiSiaddi formed a material R&D and foreign trade project team, establishing an 18-day sample optimization and rectification cycle, coordinating upstream PLA resin manufacturers and modification workshops to implement grade-by-grade optimization solutions.
HiSiaddi selected differentiated raw materials according to operating conditions of the two products:
· Heat-resistant injection molding beverage cup raw material: High optical purity PLLA blended with a small amount of PDLA stereocomplex dedicated PLA substrate. Stereocomplex crystallization boosted inherent heat distortion temperature from 59°C to 82°C.
· Ultra-thin film blowing raw material: High melt strength copolymer PLA chips with strict control of oligomer content ≤90 ppm. All incoming raw materials underwent pre-drying at 80°C for 4 hours to stabilize raw material moisture content within 0.02% and eliminate gas generation during processing caused by water.
① Dedicated film blowing modified PLA: Precisely adjusted ratios of PLA and food-grade PBAT, supplemented with small amounts of bio-based citrate plasticizers and nano-talc nucleating additives, eliminating cheap industrial auxiliaries. Post-optimization elongation at break rose from 38% to 215%, enabling stable production of 22μm ultra-thin films during high-speed extrusion without traction tearing. Traceability lists for EU food approval were provided for all additives. ② Heat-resistant injection molding PLA: Stereocompound modification system incorporating compliant plant-based antioxidants and ultra-fine activated talc, with optimized filling ratios to enhance thermal stability without sacrificing transparency. Post-modification heat distortion temperature reached 91°C, meeting the requirement of no deformation under short-term 85°C microwave heating and resistance to cracking upon drop testing at -20°C low temperature.
Two batches of samples (50kg lab trial, 300kg pilot trial) were manufactured and sent to SGS Swedish laboratories for full physical property and food migration testing.
HiSiaddi engineers were stationed at manufacturing plants to guide the separation of two independent dedicated modification lines, completely isolating general-purpose material production to eliminate cross-contamination:
1. Optimized segmented feeding: PLA resin fed via main feed throat, powder fillers and toughening additives added evenly in three segmented side streams to boost dispersion uniformity and eliminate filler agglomeration.
2. Refined zoned temperature control: Feed zone 152~158°C, melting zone 172~178°C, homogenization zone 168~173°C, die head 165°C – high-temperature zone temperatures were reduced compared to the original process to avoid thermal degradation of PLA molecular chains.
3. Dual-stage high-negative-pressure vacuum devolatilization activated for deep removal of residual small molecules and volatile impurities. Post-pelletizing low-temperature circulating hot air drying silos stabilized finished pellet moisture content below 0.012%.
HiSiaddi compiled bilingual Swedish-English operation manuals and provided one-on-one remote guidance to the client’s process engineers for equipment parameter optimization:
· Film blowing lines: Moderately lower overall barrel temperature, slow down main screw speed, reduce traction stretching rate, fine-tune die head air volume to balance film cooling and crystallization speed, resolving ultra-thin film rupture and uneven thickness defects.
· Injection molding lines: Raise mold temperature to 55°C, extend in-mold cooling time, reduce injection speed to slow product shaping and release internal molding stress, improving warpage and low-temperature cracking defects of injection molded cups.
Continuous 72-hour small-batch trial production drastically reduced defect rates for both products, with all indicators meeting standards.
The initial 65-ton stock raw material was fully returned to the factory for formula and process rectification, then shipped in two batches from Shanghai Port to Gothenburg Port, Sweden. Complete pre-prepared physical property reports enabled rapid customs clearance and warehousing. After raw material launch, yield rates of the two core production lines (film blowing and injection molding) recovered to 97.9%, enabling on-time delivery of contracted packaging orders to ICA supermarkets and avoiding approximately 36,000 EUR in scrap and breach-of-contract losses. The comprehensive procurement unit price of localized PLA decreased by 27.6% compared to original imported NatureWorks raw materials, and delivery lead times were compressed to 36 days.
Three months after rectification validation, Sweden EcoPack AB signed a 295-ton annual PLA procurement framework with HiSiaddi, locking in the two finalized optimized formulas developed by HiSiaddi. HiSiaddi undertook annual dynamic fine-tuning of raw material formulas, tracking updates to EU food regulations, and conducting pre-shipment physical property inspections for every delivery batch. The client subsequently entrusted HiSiaddi with customized formula development for a new dedicated PLA grade for low-temperature quick-freezing trays.
Building on this benchmark rectification case of a leading Nordic packaging enterprise, HiSiaddi leveraged the client’s Nordic industry network to connect with three equivalent organic food packaging companies in Norway and Finland. We replicated the full-chain technical service model of "substrate selection + formula optimization + pelletizing technical renovation + end-user process guidance", securing multiple batches of foreign trade orders for modified PLA and reinforcing HiSiaddi’s technical service barriers in the high-end Nordic biodegradable plastics sector.
Most domestic PLA modification manufacturers focus on low-cost disposable domestic packaging markets, designing mass-production formulas around low-cost generic products with limited capacity for refined R&D tailored to mid-to-high-end European and American food packaging applications. Widespread issues include crude additive selection and fixed production processes without targeted optimization. Overseas mid-to-high-end clients maintain mature processing habits built around imported raw materials, leading to mismatched process parameters after switching to domestic PLA and amplified production defects. The combination of these two factors triggers mass production failures.
Breaking away from traditional foreign trade limited to sourcing matchmaking, HiSiaddi centers material technology as its core competitive advantage, conducting full-traceability troubleshooting and rectification spanning upstream resin substrates, modified formulas, pelletizing production, and downstream end-user processing. The solution eliminated the client’s operational risks of production line shutdown and contract breach, while establishing deep binding relationships with high-quality Nordic end customers through professional technical services. Against the backdrop of normalized global plastic restrictions and increasingly stringent EU food packaging regulations, technology-enabled foreign trade represents the core pathway for domestic PLA to penetrate global mid-to-high-end green packaging supply chains.
For inquiries about formula optimization consulting services, please contact HiSiaddi customer service.
+86-13120989737 
info@hisiaddi.com 
English
