先说一个行业乱象:PBAT是这几年可降解塑料里的热门品种,市场上挂着"PBAT副牌"在卖的货,价格能差出两三成。外行一看都是淡黄色颗粒,分不清谁是谁。有人拿PLA掺点PBAT改一改当PBAT卖,有人把不同熔指的批次混着装袋。做可降解购物袋的一上机,吹膜一拉就破、横向拉伸不够,整吨料下去,破袋率高得没法交货。PBAT这东西,副牌不是不能用,是熔指和断裂伸长率不对路,吹膜线一开就出废品。
结论先说:PBAT副牌能用,但熔指和断裂伸长率必须先测,测不准就上吹膜机,整批袋子都得返工。今天把金发科技、新疆蓝山屯河、彤程新材这三家国产PBAT头部企业的副牌门道,一次讲透。
PBAT是什么?国内产能谁在跑
PBAT是己二酸丁二醇酯和对苯二甲酸丁二醇酯的共聚物,把PBA的柔韧和PBT的刚性拼在一起,既柔韧又可堆肥降解,是可降解购物袋、快递袋、农用地膜、一次性餐具的主力材料。它是改性料,常和PLA共混调硬度和透明度。
国内PBAT产能这几年扩得快,主要集中在几家。金发科技是国内可降解材料布局早、规模靠前的企业之一,广州、天津、宜宾都有基地,产品覆盖快递包装、农用地膜、一次性制品;新疆蓝山屯河在新疆昌吉,依托煤化工和乙二醇资源,PBAT/PBS一体化,成本有优势;彤程新材在上海化工园区,是国内少有的获巴斯夫授权使用其专有技术及设备的PBAT生产企业,产品定位高端可降解制品。此外万华化学、恒力石化也是重要产能方,行业开工率随政策和订单波动较大。
PBAT副牌:熔指和断裂伸长率是两道坎
PBAT副牌,是原厂同一牌号体系里检验指标小幅偏离的批次。落到PBAT上,副牌最常见的差异点集中在四项:熔指波动、断裂伸长率偏低、色相偏黄、含水率偏高。
为什么这几项关键?吹膜和流延对熔指很敏感,熔指高了膜发脆、低了膜起皱;断裂伸长率直接决定袋子耐不耐撕,这一项偏了,购物袋装重一点就破;含水率高了,加工时起泡、膜面有晶点。做可降解膜,配方是按熔指卡着调的,副牌熔指差一档,工艺就得跟着改。
和回料的区别:PBAT回料是边角膜、废品袋破碎再造粒,已经受过一次热历史,分子量下降、降解性能打折;PBAT副牌是原厂原生聚合粒子,只是个别指标小幅偏离。做购物袋,用副牌是"熔指够不够吹膜"的问题,用回料是"降解和强度过不过"的问题。
金发科技:国产可降解材料的规模担当
金发科技在广州,是国内改性塑料和可降解材料布局较早、规模靠前的企业。它的PBAT产品在快递包装、农用地膜、一次性餐饮三个方向都有成熟牌号,广州、天津、宜宾多基地协同供货,下游客户覆盖不少可降解制品厂。
金发副牌料的特点是:牌号体系齐全,吹膜级和流延级都有;大厂批次管理规范,熔指记录完整;副牌以熔指和色相小幅偏离为主,适合对成本敏感、配方容忍度较高的购物袋、垃圾袋、地膜制品。高端认证餐饮级仍建议正牌。
适用场景:可降解购物袋、快递袋、农用地膜、一次性餐具、流延膜。
新疆蓝山屯河:煤化工一体化的成本路线
蓝山屯河在新疆昌吉,依托当地煤化工和乙二醇原料,走PBAT/PBS一体化路线,原料自给让成本控制有优势。它的PBAT产品在西北、华北可降解制品圈有稳定客户,也出口中亚市场。
蓝山屯河副牌料的特点是:原料自供带来成本竞争力,副牌价格有吸引力;产品以吹膜级和通用注塑级为主;缺点是新疆基地到华东华南运距长,交货周期和运费要提前算,适合批量大、不赶急单的地膜和垃圾袋制品。
适用场景:农用地膜、垃圾袋、一次性制品、通用注塑件。
彤程新材:巴斯夫技术授权的高端路线
彤程新材在上海化工园区,是国内少有的获巴斯夫授权使用其专有技术及指定设备的PBAT生产企业,一期实际建成产能数万吨,产品定位高端可降解制品,购物袋、快递袋、农用地膜都覆盖。
彤程副牌料的特点是:技术授权背景,产品一致性和高端制品口碑好;华东区位,长三角客户提货距离近;副牌多来自中高端牌号的熔指小幅波动,适合要求膜面外观和降解性能稳定的中高端包装制品。
适用场景:高端可降解购物袋、快递袋、透明包装膜、一次性制品。
PBAT副牌避坑指南
第一,先测熔指再上机。PBAT副牌熔指波动比正牌大,吹膜线换料前先做小试,确认熔指在配方窗口内,别拿高熔指副牌硬吹厚膜。
第二,断裂伸长率必看。这一项直接关系袋子耐撕不耐撕,副牌要随货看检测单,伸长率不达标的别上购物袋。
第三,水分要控。PBAT吸潮,加工前要干燥,含水率高的批次膜面起泡、有晶点。
第四,食品接触和堆肥认证件别用副牌。有食品接触或工业堆肥认证要求的PBAT制品,必须用正牌并保留认证,副牌只用于一般包装和非认证地膜。
科隆仓库现货|国产PBAT吹膜常备
科隆在宁波仓库常备国产PBAT副牌现货,主推品牌覆盖金发科技、新疆蓝山屯河、彤程新材三家国内头部企业。主要牌号涵盖吹膜级、流延级、注塑级多个常用型号,包装分大包装与小包装两种,不同用途按制品厂配方混搭备货。
仓库现货通常在5000吨左右:小包副牌备货800-1000吨,箱装副牌备货300-500吨,大包料/吨包料备货3500-3900吨。
供应保障走先测后签:每批PBAT副牌料到货先抽测熔指、断裂伸长率、含水率三项关键指标,测试合格再签合同;袋子厂换料前科隆可先提供小样做吹膜验证,通过后再批量切料。
选型口诀与案例
国产PBAT副牌怎么选?记住四句话:熔指先测再上机,伸长率要看检测单,水分加工前控住,认证件不碰副牌。
青岛一家做可降解购物袋的制品厂,原来一直用某进口PBAT正牌吹膜,每吨成本压不下来。今年改用科隆供的金发科技PBAT副牌吹膜级,先拿两吨小样测熔指和断裂伸长率,都落在原配方窗口里,批量上机后膜面均匀、破袋率没涨,成品通过堆肥降解检测,每吨原料成本降了近一千八百元。厂长说:做普通购物袋又不是食品接触认证件,熔指够、伸长率稳,为什么要花进口正牌的钱?
First, let's talk about an industry chaos: PBAT has been a hot product among biodegradable plastics in recent years. Goods sold under the "PBAT sub-brand" label can differ by 20-30%. Outsiders see they are all pale yellow pellets, making it hard to tell which is who. Some people add some PLA and modify PBAT to sell as PBAT, while others mix batches of different melting fingers for bagging. When making biodegradable shopping bags is put on the machine, the film tears with a single pull, and the lateral stretching is insufficient. After a full ton of material, the breakage rate is so high that delivery is impossible. PBAT isn't unusable as a secondary brand, but the melting fingers and elongation at break are not aligned, so as soon as the film blowing line opens, it produces scrap.
Conclusion First: PBAT sub-brands can be used, but melt fingers and elongation at break must be tested first. If not accurate, they're put on a film blowing machine, and the entire batch of bags has to be reworked. Today, I'll thoroughly explain the sub-brand secrets of three leading domestic PBAT companies: Kingfa Technology, Xinjiang Lanshan Tunhe, and Tongcheng New Materials. What is
PBAT? Who is running domestic production capacity
PBAT it's a copolymer of butylene adidiol adiate and butylene terephthalate, combining the flexibility of PBA with the rigidity of PBT. It is both flexible and compostable and biodegradable, making it the main material for degradable shopping bags, courier bags, agricultural mulch film, and disposable tableware. It is a modified material often blended with PLA to adjust hardness and transparency.
Domestic PBAT capacity has expanded rapidly in recent years, mainly concentrated in a few companies. Kingfa Technology is one of the earliest and largest-scale domestic companies in biodegradable materials, with bases in Guangzhou, Tianjin, and Yibin, covering express packaging, agricultural mulch film, and disposable products; Xinjiang Lanshan Tunhe is in Changji, Xinjiang, relying on coal chemical and ethylene glycol resources, integrating PBAT and PBS with cost advantages; Tongcheng New Materials is in the Shanghai Chemical Park, one of the few PBAT manufacturers authorized by BASF to use its proprietary technology and equipment, with products positioned as high-end biodegradable products. In addition, Wanhua Chemical and Hengli Petrochemical are also important capacity players, with industry operating rates fluctuating greatly with policies and orders.
PBAT sub-brand: The melt finger and elongation at break are
PBAT two key hurdles. For sub-brands, they are batches with slight deviations in inspection indicators within the same original grade system. For PBAT, the most common differences among sub-brands are concentrated in four items: fluctuation in the melt finger, lower elongation at break, yellowish hue, and higher moisture content.
Why are these key points? Film blowing and casting are very sensitive to the melt fingers; if the melt index is high, the film becomes brittle; if low, the film wrinkles; The elongation at break directly determines whether the bag is tear-resistant. If this is deviated, the shopping bag will tear if it's heavier; If the moisture content is high, bubbling occurs during processing and the film surface shows crystal spots. For biodegradable films, the formula is adjusted according to the melting fingers; if the secondary brand's melting finger is a notch lower, the process must be adjusted accordingly.
Difference from recycled materials: PBAT recycled material is made by crushing the edge cornea and waste bags into pellets, having undergone a thermal cycle, resulting in reduced molecular weight and reduced degradability; PBAT secondary brand is original factory polymer particles, with only slight deviations in certain indicators. For shopping bags, using secondary brands is a matter of "melt fingers sufficient to blow the film," while recycled materials are a matter of "degradability and strength tolerance."
Kingfa Technology: The scale leader of domestic biodegradable materials
Kingfa Technology is one of the earliest and largest-scale domestic companies in modified plastics and biodegradable materials in Guangzhou. Its PBAT products have mature grades in express packaging, agricultural mulch film, and disposable catering, with coordinated supply from multiple bases in Guangzhou, Tianjin, and Yibin, and downstream customers covering many biodegradable product factories. The characteristics of
Jinfa sub-brand material are: a complete grade system, including both blown film and cast grade grades; Large factories have standardized batch management with complete melting finger records; Sub-brands mainly have melting fingers and slight color deviations, suitable for shopping bags, garbage bags, and mulch film products sensitive to cost and high formula tolerance. High-end certified catering grades are still recommended for genuine products.
Applicable scenarios: biodegradable shopping bags, express bags, agricultural mulch film, disposable tableware, cast film.
Lanshantunhe, Xinjiang: Cost route for coal chemical integration
Lanshantunhe is in Changji, Xinjiang, relying on local coal chemical and ethylene glycol raw materials, following an integrated PBAT/PBS route, with self-sufficiency in raw materials giving cost control advantages. Its PBAT products have stable customers in the biodegradable product circles in Northwest and North China and are also exported to the Central Asian market.
Lanshantunhe's secondary brand material features are: self-supply of raw materials brings cost competitiveness, and subbrand prices are attractive; Products mainly use blown film grade and general injection molding grade; The disadvantage is that the Xinjiang base has long transportation distances from East and South China, delivery cycles and shipping costs must be calculated in advance, suitable for large batches and non-urgent plastic film and garbage bag products.
Applicable scenarios: agricultural mulch film, garbage bags, disposable products, general injection molded parts.
Tongcheng New Materials: BASF's technology licensing high-end route
Tongcheng New Materials is located in the Shanghai Chemical Park, one of the few PBAT manufacturers in China authorized by BASF to use its proprietary technology and designated equipment. The first phase has an actual built capacity of tens of thousands of tons, with products positioned as high-end biodegradable products, covering shopping bags, courier bags, and agricultural mulch films. The characteristics of
Tongcheng sub-brand materials are: technical licensing background, product consistency, and a good reputation for high-end products; Located in East China, with close delivery distances to customers in the Yangtze River Delta; Sub-brands mostly come from mid-to-high-end grades with slight melting index fluctuations, suitable for mid-to-high-end packaging products requiring stable film appearance and degradation performance.
Applicable scenarios: high-end biodegradable shopping bags, courier bags, transparent packaging films, disposable products.
PBAT secondary brand pitfall guide
First, test the melting index before machine use. PBAT secondary brand melt index fluctuates more than genuine brand. Before changing material on the film blown film line, conduct a small test to confirm the melting index is within the formula window. Do not force thick film with high melting index secondary brand.
Second, check the breaking elongation rate. This point directly affects whether the bag is tear-resistant. Check the inspection report for sub-brand products; if elongation does not meet standards, do not use shopping bags.
Third, control moisture. PBAT absorbs moisture; dry it before processing; batches with high moisture content may have bubbling or crystal dots on the film surface.
Fourth, food contact and composting certification items should not use sub-brands. PBAT products requiring food contact or industrial composting certification must use genuine brands and retain certification; sub-brands are only used for general packaging and non-certified mulch films.
Cologne warehouse in-stock | Domestic PBAT blow-film in stock
Cologne maintains domestic PBAT sub-brand stock at its Ningbo warehouse, with main brands covering three leading domestic companies: Kingfa Technology, Xinjiang Lanshan Tunhe, and Tongcheng New Materials. Main grades include blown film-grade, cast cast, and injection molding grades, with packaging available in large and small sizes, mixed according to factory formulas for different uses.
Warehouse stock is usually around 5000 tons: small sub-brand stock 800-1000 tons, boxed sub-brand stock 300-500 tons, large bulk material per ton 3500-3900 tons.
Supply assurance follows a first-test-then-sign approach: each batch of PBAT sub-brand material is sampled for melt index, elongation at break, and moisture content, and only after passing tests is contract signed. Before bag factories change materials, Cologne can provide samples for film blowing verification, and after passing, batch cutting proceeds.
Selection tips and case studies
How to choose domestic PBAT sub-brands? Remember these four points: test the melting index before machine use, check the elongation rate according to the inspection report, control moisture before processing, and ensure certified parts don't touch the secondary brand.
A factory in Qingdao that makes biodegradable shopping bags used to use a certain imported PBAT genuine brand blown film, which couldn't reduce the cost per ton. This year, they switched to using Kingfa Technology's secondary brand blow-blown film supplied by Cologne. They first took two tons of samples to measure melt fingers and elongation at break, all in the original formula window. After batch production, the film surface was uniform and the bag breakage rate didn't increase. The finished product passed compost degradation testing, and the raw material cost per ton dropped by nearly 1,800 yuan. The factory director said: Making ordinary shopping bags isn't a food contact certified part. The melting finger is sufficient and the elongation is stable. Why spend money on imported genuine brands?