做食品包装、做汽车燃油系统、做医用包装的老板都知道EVOH这个料——阻氧性极强，包装行业的"高阻隔之王"。但长期以来，EVOH市场被日本可乐丽一家独大，三菱化学和台湾长春石化分一杯羹，国内工厂只能接受人家的报价和交期。一包EVOH正牌料到厂，价格高、货期长、还得排队。2024年年中，这个局面终于被打破了。
EVOH是什么 国产化为什么这么难
EVOH（乙烯-乙烯醇共聚物）是一种兼具乙烯链段疏水性和乙烯醇链段阻氧性的高阻隔材料。它的核心价值在于阻氧——氧气透过率比PE低两个数量级，广泛用于多层共挤食品包装膜、汽车燃油系统阻隔层、医用包装等。全球EVOH技术门槛极高，截至2024年末，全球仅有4家企业具备规模化生产能力：日本可乐丽、日本合成化学（三菱化学体系）、中国台湾长春石化和中石化川维。其中可乐丽和三菱化学合计贡献超80%产能。
国产化难在哪？EVOH的核心工艺是乙烯-醋酸乙烯共聚物（EVA）的部分醇解，醇解度控制精度要求极高，直接影响阻氧性能。川维化工依托自身在PVA（聚乙烯醇）领域的技术积累——川维是国内最大的PVA生产基地之一——将PVA的醇解技术延伸到EVOH，才最终突破了这个瓶颈。
2024年6-7月，中石化川维1.2万吨/年EVOH工业化装置完成调试，正式投产批量出货，填补了中国大陆EVOH大规模工业化生产的空白。之后川维又启动了2.4万吨/年技术升级项目，建成后总产能将达到3.6万吨/年。此外，皖维高新6000吨/年EVOH项目已于2024年8月环评公示，万华化学2万吨EVOH装置预计2026年投产，国产化进程正在加速。
EVOH副牌的特殊性 醇解度是生命线
EVOH副牌和其他品类副牌最大的区别在于：EVOH的核心指标是乙烯含量和醇解度，这两个参数直接决定阻氧性能。副牌EVOH通常是乙烯含量或醇解度在标称值附近小幅波动，比如标称32mol%乙烯含量的牌号，副牌可能在30%-34%之间浮动。这个偏差在普通包装应用中可以接受，但在高阻隔要求的食品包装和燃油系统中需要谨慎评估。
EVOH副牌来源仍是四大类：开停车头尾料、牌号切换过渡料、工艺波动导致醇解度小幅偏离的批次、副线尾料。川维作为新投产装置，工艺爬坡期的过渡料和头尾料相对较多，这是当前国产EVOH副牌的主要来源。
和回料的区别：EVOH回料经过再次挤出后，乙烯醇链段可能发生热降解，阻氧性能下降明显。副牌EVOH是原厂原生粒子，分子结构完整，只是醇解度略有偏差。对于做非食品级包装、一般工业阻隔层的客户，副牌EVOH的性能足够。
中石化川维化工 国内EVOH工业化破局者
中石化川维化工位于重庆，是中国石化旗下以天然气化工为基础的大型化工企业，也是国内PVA（聚乙烯醇）行业的龙头。川维依托PVA醇解技术积累，从2011年前后开始布局EVOH业务，经过十余年研发，于2024年6-7月完成1.2万吨/年工业化装置的调试和批量出货。
川维EVOH的核心竞争力在于PVA- EVOH一体化：川维自身生产PVA，EVOH生产所需的EVA前体可以实现内部配套，成本控制能力强于纯外购原料的企业。产品定位对标可乐丽F系列，已在食品包装、汽车燃油系统等领域获得客户验证。
副牌方面，川维EVOH副牌目前以小包装为主，主要来源于装置投产初期的工艺过渡料和牌号切换料。对于做工业包装阻隔层、一般日用品包装的客户，川维副牌EVOH是目前唯一的国产原生料选择。第二梯队方面，皖维高新6000吨EVOH项目正在建设中，万华化学2万吨EVOH装置预计2026年投产，届时国产EVOH供应格局将进一步丰富。
EVOH副牌进厂 阻氧性必须实测
第一，测阻氧性能。EVOH副牌最关键的指标就是氧气透过率（OTR）。进货前要求供应商提供同批次OTR检测数据，到货后用透氧仪复测。如果OTR超出你的产品允许范围，阻氧功能就打了折扣。对于食品包装应用，建议先打样做整体阻氧验证。
第二，确认乙烯含量。EVOH不同乙烯含量对应不同的加工温度和阻氧特性。副牌EVOH的乙烯含量偏差可能导致加工温度窗口变化，需要调整挤出工艺。进货时确认乙烯含量偏差范围，避免上了机才发现温度不对。
第三，按应用分级。食品级高阻隔包装用正牌EVOH稳妥，工业包装、非直接接触阻隔层可以用副牌。不要拿副牌EVOH去做要求严格的食品包装——阻氧性差一点，食品保质期就短一截，出了问题不是材料钱能兜住的。
科隆仓库现货 国产EVOH副牌国内独供
科隆仓库现货EVOH副牌，主推中石化川维化工产国产EVOH树脂，主要牌号覆盖通用级和工业级，以小包装为主。仓库现货通常在4000吨上下，其中小包副牌备货600-900吨、箱装副牌备货250-450吨、大包料/吨包料备货2650-3150吨。供应保障走检测单随货通道，每批货附带原厂出厂检测单（含乙烯含量、醇解度、OTR数据），支持到货复检。
Anyone in food packaging, automotive fuel systems, or medical packaging knows EVOH—extremely strong oxygen barrier and the "king of high barrier" in the packaging industry. But for a long time, the EVOH market has been dominated solely by Japan's Kuraray, with Mitsubishi Chemical and Taiwan's Changchun Petrochemical sharing a share, while domestic factories can only accept their quotes and delivery times. A package of genuine EVOH material arrives at the factory, but the price is high, lead times are long, and there are queues. By mid-2024, this situation was finally broken. What is
EVOH? Why is localization so difficult
EVOH (Ethylene-vinyl alcohol copolymer) is a high-barrier material that combines hydrophobicity at the ethylene chain segment and oxygen barrier at the vinyl alcohol segment. Its core value lies in oxygen barrier—its oxygen permeability is two orders of magnitude lower than PE, and it is widely used in multilayer co-extruded food packaging films, automotive fuel system barriers, medical packaging, and more. The global EVOH technology threshold is extremely high. As of the end of 2024, only four companies worldwide have large-scale production capabilities: Japan's Kuraray, Japan's Synthetic Chemical (Mitsubishi Chemical system), Taiwan's Changchun Petrochemical, and Sinopec's Chuanwei. Among them, Kuraray and Mitsubishi Chemical together contribute over 80% of production capacity.
What makes localization difficult? The core EVOH process is partial alcoholism of ethylene-vinyl acetate copolymer (EVA), which requires extremely high precision in alcohol incorporation control, directly affecting oxygen barrier performance. Chuanwei Chemical leveraged its own technical accumulation in PVA (polyvinyl alcohol)—Chuanwei is one of the largest PVA production bases in China—to extend PVA alcohol lysis technology to EVOH, ultimately overcoming this bottleneck.
In June-July 2024, Sinopec Chuanwei's 12,000-ton/year EVOH industrialized unit completed commissioning and officially started mass production, filling the gap in large-scale EVOH production in China mainland. Subsequently, Chuanwei launched a 24,000-ton/year technology upgrade project, with a total capacity of 36,000 tons/year upon completion. Additionally, Wanwei High-Tech's 6,000-ton/year EVOH project was announced in environmental impact assessment in August 2024, and Wanhua Chemical's 20,000-ton/year EVOH unit is expected to start production in 2026, accelerating the localization process.
EVOH Specialties of Sub-Brands Alcohol Lysis is a lifeline
EVOH The biggest difference between sub-brands and other sub-brands is that the core indicators of EVOH are ethylene content and alcohollysis, which directly determine oxygen barrier performance. Sub-brand EVOH usually has slight fluctuations in ethylene content or alcohol incorporation near the nominal value; for example, a grade nominally rated at 32 mol% ethylene may fluctuate between 30% and 34%. This deviation is acceptable in general packaging applications but requires careful evaluation in food packaging and fuel systems with high barrier requirements.
EVOH sub-brand sources still fall into four main categories: start-stop starting and tail materials, grade switching transition materials, batches with slight deviations in alcohol incorporation caused by process fluctuations, and secondary line tailings. As a newly commissioned unit, Chuanwei has relatively more transition and tail materials during the process ramp-up phase, which are currently the main source of domestic EVOH sub-brands. Difference between
and recirculation: After EVOH re-extrud, the vinyl alcohol chain segment may undergo thermal degradation, significantly reducing oxygen resistance. Sub-brand EVOH is original factory native particles with intact molecular structure, only slightly different in alcohol incorporation. For customers making non-food-grade packaging and general industrial barrier layers, sub-brand EVOH performs sufficiently.
Sinopec Chuanwei Chemical The domestic EVOH industrialization breakthrough
Sinopec Chuanwei Chemical is located in Chongqing and is a large chemical enterprise under Sinopec based on natural gas chemical industry, also a leader in China's PVA (polyvinyl alcohol) industry. Relying on PVA alcohol lysis technology accumulation, Chuanwei began its EVOH business around 2011. After more than ten years of R&D, it completed commissioning and mass shipment of a 12,000-ton/year industrial unit in June-July 2024.
Chuanwei EVOH's core competitiveness lies in PVA-EVOH integration: Chuanwei produces PVA itself, and EVA precursors required for EVOH production can be internally supported, giving it stronger cost control capabilities than purely purchased raw materials. Product positioning targets the Kuraray F series and has been validated by customers in food packaging, automotive fuel systems, and other fields.
Regarding sub-brand, Chuanwei EVOH's sub-brand currently mainly focuses on small packages, primarily from process transition materials and grade switching materials during the initial stage of unit operation. For customers making industrial packaging barriers and general daily necessities packaging, Chuanwei's sub-brand EVOH is currently the only domestic virgin material choice. For the second tier, Wanwei High-tech's 6,000-ton EVOH project is under construction, and Wanhua Chemical's 20,000-ton EVOH unit is expected to start production in 2026, further enriching the domestic EVOH supply landscape.
EVOH sub-brand entering the factory, oxygen resistance must be tested
First, test oxygen barrier performance. The most critical indicator for EVOH sub-brand is oxygen permeability (OTR). Before purchase, suppliers are required to provide OTR test data for the same batch, and after arrival, retest with an oxygen permeability test. If OTR exceeds your product's allowable range, the oxygen barrier function is compromised. For food packaging applications, it is recommended to first conduct samples for overall oxygen resistance verification.
Second, confirm the ethylene content. Different EVOH ethylene contents correspond to different processing temperatures and oxygen barrier characteristics. Ethylene content deviations in sub-brand EVOH may cause changes in processing temperature windows, requiring adjustment to the extrusion process. Check the ethylene content deviation range when purchasing to avoid discovering temperature errors only after machine loading.
Third, classify by application. Food-grade high-barrier packaging should use genuine EVOH for safety; industrial packaging and non-direct contact barrier layers can use sub-brand. Do not use sub-brand EVOH for strict food packaging—weaker oxygen barrier means shorter shelf life, and problems cannot be covered by material costs.
Cologne warehouse in-stock domestic EVOH sub-brand supply exclusively
Cologne warehouse in-stock EVOH sub-brand, mainly promoting Sinopec Chuanwei Chemical's domestic EVOH resin, mainly covering general and industrial grades, mainly small packages. Warehouse stock is usually around 4,000 tons, with 600-900 tons of sub-label stocked for small parcels, 250-450 tons for sub-label containers, and 2,650-3,150 tons for large packages/ton. Supply assurance is provided through the inspection order channel, with each batch accompanied by the original factory test report (including ethylene content, alcohol incorporation, OTR data), and supports re-inspection upon arrival
