As a new-type foreign trade service provider driven by dual engines of technology commercialization and foreign trade services, HiSiaddi has established a "1+2+3+4=1" service system and can supply polyimide products from multiple well-known original manufacturers. With over a decade of market experience as a foreign trader with R&D capabilities, HiSiaddi possesses rich experience addressing product compliance issues through technological transformation cooperation with factories. Below is a case of HiSiaddi resolving polyimide product compliance challenges.
Please contact HiSiaddi customer service if you wish to consult more polyimide product compliance issues.
The cooperating buyer is Railtech Italia Srl based in Milan, Italy, a specialized and sophisticated rail transit manufacturing enterprise rooted in Italy, serving as a primary supporting supplier of on-board interior and electronic control components for Ferrovie dello Stato Italiane (FS) and Alstom Locomotives. With 28 years of experience in R&D and production of high-temperature resistant insulating parts for locomotive traction systems, on-board electronic control module PI structural parts, and flame-retardant circuit isolation films for trains, it belongs to the mid-to-high-end premium customer tier for rail transit polyimide procurement. The enterprise previously sourced PI raw materials long-term from European branches of DuPont and Ube Industries for rail-specified modified PI. In 2025, impacted by rising chemical raw material prices in Europe and extended customized delivery cycles exceeding 90 days for overseas major manufacturers, the enterprise’s supply chain department contacted HiSiaddi New Materials Foreign Trade based in Shanghai via the European Rail Transit Materials Association, reaching cooperation for customized flame-retardant modified thermoplastic PI injection molded parts for rail transit and low-smoke halogen-free PI insulating films. The initial order covered a total procurement volume of 560 kg of two major product categories, all applied to on-board electronic control components of Italy’s new-generation intercity EMUs.
Having long relied on European suppliers to handle full sets of EU compliance documents, the customer was completely unfamiliar with dual domestic and overseas compliance rules covering Chinese chemical export customs clearance, EU REACH, EN45545 rail transit flame retardant certification, and Italian customs chemical import filing. The customer previously independently contacted two domestic PI manufacturers for sample preparation and stock preparation, yet four linked compliance obstacles emerged approaching shipment: missing certifications, excessive restricted substance content, non-standard customs declaration documents, and absent pre-registration for EU destination countries, risking inability to export goods and customs detention or destruction upon arrival in Italy, bringing the project delivery close to breach of contract. The customer fully entrusted HiSiaddi to conduct full-chain compliance rectification and customs clearance delivery.
This batch of products consists of high-end rail transit dedicated flame-retardant modified PI, subject to stringent EU locomotive access standards, with far higher environmental protection, flame retardancy, and chemical control thresholds than ordinary industrial goods, distinct from low-grade civil electrical insulation PI.
Alstom mandates that locomotive components must be accompanied by EU EN45545-2 rail transit flame retardant classification certification (Grade R1). Previously cooperating domestic manufacturers only held conventional UL94 flame retardant reports tested under Chinese national standards, unrecognized by the EU rail transit system. Without official EN45545 certification documents issued by EU Notified Bodies (NB), products cannot be added to Alstom’s supplier list even if physical and chemical performance meets standards, and goods cannot be installed on vehicles upon arrival in Italy. While the customer’s original European and American suppliers pre-provided full EU qualification documents, most domestic PI manufacturers lack specialized third-party EU rail transit certifications, forming the primary compliance bottleneck of this project.
The latest version of the EU REACH SVHC control list expands to over 230 restricted chemical substances. Third-party sampling testing of early customer samples detected two substances (trace organic plasticizers and heavy metal components) exceeding limit values within PI modified fillers. Production control of some domestic PI manufacturers follows general industrial standards without pre-screening raw materials per full-item EU REACH restricted substance standards. Direct shipment of such products will result in full-container detention, return, or harmless destruction upon customs inspection in Italy, incurring high port detention and return costs. Unfamiliar with detailed REACH substance control provisions, the customer cannot guide factories to adjust formulas and raw material selection.
Domestic cooperating manufacturers handled chemical exports for the first time, compiling MSDS chemical safety instructions under outdated domestic specifications with inconsistent chemical names, CAS numbers, component proportions, and HS code declaration content. As PI belongs to fine polymer chemicals, customs commodity inspection requires component traceability documents, production feeding ledgers, and factory COA quality inspection reports. Original document formats failed to meet China customs exit commodity inspection specifications, resulting in preliminary inspection rejection and preventing goods from normal customs clearance and loading. Based overseas, the customer could not coordinate factory document rectification within China, and independent third-party customs broker quotations were exorbitant with insufficient chemical professional expertise.
EU member states have added localized control regulations on top of REACH. Italy implements localized K-REACH pre-registration systems, requiring advance import entity filing and product pre-declaration for chemical raw materials entering Italy from non-EU countries. Previously relying on local European suppliers to complete pre-registration, the customer lacked local compliance agents for direct procurement from China for the first time, without which goods cannot complete customs clearance upon arrival.
All four compliance challenges are exclusive access thresholds for high-end rail transit PI exported to the EU. Most low-grade civil PI exports only require basic commodity inspection without specialized EU rail flame retardant certification, full REACH screening, and localized destination country pre-registration, forming the most common compliance pitfalls for overseas mid-to-high-end customers switching to domestic procurement.
HiSiaddi’s technical compliance team cross-referenced the latest REACH-SVHC control list and chemical limit values of EN45545 rail transit materials to guide production-side formula adjustment in reverse: First, eliminate restricted organic flame retardant additives and non-standard inorganic fillers in the original formula, replacing them with EU-certified halogen-free phosphorus-based flame retardant powder and compliant high-purity boron nitride modified fillers. All auxiliary material suppliers provided REACH compliance statements and COA test certificates for auxiliary materials. Second, all PI polymerization monomers were selected from high-purity raw materials eligible for EU market access, eliminating industrial-grade monomers containing trace heavy metal impurities, with impurity extraction procedures added during synthesis. Three rounds of formula sample testing were completed successively, with two previously over-limit substances rectified to within threshold values after full-item SVHC screening at SGS EU laboratories, issuing full REACH test reports complying with EU standards to eliminate environmental compliance risks originating from product formulas. Simultaneously, flame retardant ratios were fine-tuned aligned with customer vehicle loading conditions to retain original temperature resistance and insulation performance while meeting Grade R1 fire resistance indicators.
HiSiaddi coordinated with EU local NB notified certification bodies to arrange product sample testing per EN45545-2 Grade R1 test standards, coordinating three core rail transit tests covering flame retardancy, smoke density, and toxic flue gas. Full progress tracking of laboratory testing was maintained, and PI matrix copolymer ratios plus filler addition proportions were optimized to address minor smoke density over-limit issues, successfully obtaining official EN45545 certification certificates and English test reports issued by EU notified bodies after 36 days. Key product technical parameters were sorted out simultaneously, and certification information was entered into Alstom’s supplier raw material filing system to meet customer end vehicle loading access compliance requirements.
To prevent recurrence of raw material compliance out-of-control risks, HiSiaddi re-screened two domestic mid-to-high-end manufacturers specializing in rail transit PI, both holding IATF16949 quality management systems and long-term supporting domestic high-speed rail OEMs. Complete chemical compliance ledgers are established throughout raw material procurement, production feeding, and finished product delivery, with compliance statements attached to all incoming auxiliary materials. Previously small and medium-sized manufacturers with imperfect compliance control systems were discarded. A dedicated dust-free production workshop for rail-grade PI was designated throughout production, with raw material traceability documents and factory full-item quality inspection reports retained for each batch of finished products. Key performance indicators of finished products were benchmarked against DuPont rail-grade PI used by the customer, with performance deviation controlled within 3%. Compliance standards were fully met while reducing the customer’s procurement cost by 28.6% compared with imported raw materials.
First, Rectification of domestic export documents: HiSiaddi compliance specialists revised MSDS in accordance with the Globally Harmonized System of Classification and Labelling of Chemicals (GHS), unifying CAS numbers, chemical composition proportions, and hazard classifications. Original factory feeding ledgers, COA quality inspection reports, and material traceability lists were sorted out, and HS customs code declaration content standardized to pass domestic customs exit commodity inspection and customs clearance review in a single round, enabling smooth container loading and shipment. Second, Delivery of Italian import compliance: Leveraging cooperative European compliance agencies, HiSiaddi assisted the customer in completing Italian K-REACH product pre-registration and filing of local Italian compliance agents. REACH reports, EN45545 certifications, certificates of origin, and English commodity inspection documents were submitted to Italian customs for pre-review in advance, enabling rapid customs clearance upon goods arrival without port inspection and detention. Third, Compliance control of product packaging: Goods were vacuum aluminum foil anti-static sealed and packed in accordance with EU dangerous goods packaging specifications, with EU compliance labels and chemical hazard warning labels printed on outer cartons to avoid customs detention in destination countries due to non-compliant packaging.
1. Timely Performance of Initial Order: The full 560 kg batch of flame-retardant modified PI injection molded parts plus 2,100 ㎡ low-smoke PI insulating films were delivered to Milan, Italy on schedule. Full incoming review of REACH and fire protection compliance documents at the customer’s facility yielded complete and valid results, with products smoothly passing incoming inspection at Ferrovie dello Stato Italiane (FS) Italy National Rail and mass-produced in electronic control components of new-generation intercity EMUs, completely resolving risks of order breach caused by previous compliance failures.
2. Signing of Long-Term Framework Cooperation Agreement: Half a year after project delivery, the two parties signed an annual framework procurement agreement for rail transit PI, with the total annual procurement volume of various modified PI reaching 4.3 tons. The customer later added two new customized products for R&D: high-temperature resistant PI wear-resistant accessories for metro traction systems and special PI films for locomotive busbar insulation, all entrusted to HiSiaddi for coordinated product production and full-chain compliance services.
3. Optimization of Customer Procurement Model: Railtech Italia officially designated HiSiaddi as its exclusive compliance procurement service provider for China. All subsequent domestic PI raw material procurement by the customer will undergo pre-compliance review by HiSiaddi. Relying on HiSiaddi’s mature capabilities in EU compliance delivery, the customer continues to expand its domestic high-end PI supply chain, breaking its long-term sole reliance on European, American, and Japanese chemical giants for raw material procurement. The customer also leveraged its industry resources to refer two other leading Italian rail transit enterprises to conduct PI procurement cooperation.
This project focused entirely on high-end flame-retardant modified polyimide dedicated to rail transit locomotives supporting European high-speed rail complete vehicles, subject to dual constraints of multiple EU regulations and vehicle manufacturer access specifications, with a highly complex compliance system and high rectification costs, fundamentally distinct from simple export compliance for low-grade civil insulating PI. Breaking the traditional foreign trade business model limited to order receiving and delivery, HiSiaddi resolved full-chain compliance challenges covering formula rectification, certification processing, document optimization, and overseas pre-registration through dual professional capabilities in chemical engineering and cross-border compliance. It built core competitiveness for mid-to-high-end chemical foreign trade via supporting compliance services, emerging as a reliable cooperative partner for overseas mid-to-high-end manufacturing enterprises switching to domestic raw material procurement.
Please contact HiSiaddi customer service if you wish to consult more polyimide product compliance issues.
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