甩一组数据：热熔压敏胶圈子里，标签胶、卫生巾背胶、双面胶用的SIS（苯乙烯-异戊二烯-苯乙烯嵌段共聚物），国产货源集中度极高——巴陵石化一家就占了国内大半。可市场上挂"SIS副牌"在卖的货，初粘忽高忽低、持粘一压就脱胶，做出来的标签贴上去三天就翘边。SIS这东西，S/I比和溶液粘度差一点，胶的初粘和持粘就两回事。数据摆在这里，副牌怎么选，先得把SIS的门道捋顺。
结论先说：国产SIS副牌能用，但S/I比和溶液粘度必须先对胶型，国内SIS产业化主力就是中石化巴陵石化这一家。
SIS是什么？国产热塑橡胶格局
SIS是苯乙烯-异戊二烯-苯乙烯嵌段共聚物，和SBS同门，但中间段用异戊二烯。它粘度低、初粘好、涂布方便，是热熔压敏胶的主力弹性体，大量用于标签胶、卫生巾和纸尿裤背胶、双面胶、胶带、包装胶，也做塑料和沥青改性。它比SBS更软、初粘更好，但耐热和耐油性一般，主要用在不干胶和卫生用品方向。
国产SBS/SBC体系集中在巴陵石化。行业口径，巴陵石化（岳阳，现隶属中石化湖南石油化工体系）SIS年产能数万吨级，湖南基地与上海（2025年投产新增SIS六万吨）协同，牌号如YH-1106、YH-1108、YH-4016（星形）等在热熔压敏胶圈流通多年，S/I比和线性/星形结构齐全。按国内独资主力口径，巴陵石化是绕不开的一家。其余国产SIS产能仍在起步，构不成稳定货源。
SIS副牌：S/I比和溶液粘度是两道闸门
SIS副牌，是原厂同一牌号体系里出厂检验个别指标小幅偏离的批次。落到SIS上，副牌最常见的差异点集中在四项：S/I比偏差、溶液粘度波动、初粘/持粘下降、色相偏黄。
为什么这几项关键？SIS做热熔压敏胶，S/I比决定软硬和粘接，S比高了胶硬、粘力弱，I比高了胶软、耐热差；溶液粘度决定涂布工艺和上胶量，粘度不对，胶涂不匀。做标签胶，初粘和持粘是一对平衡，副牌这两项偏了，标签贴上去就翘边或脱胶。
和回料的区别：SIS回料是胶块、胶边破碎再造，已经受过一次热历史，粘接性能掉档；SIS副牌是原厂原生嵌段粒子，只是个别指标小幅偏离。做标签压敏胶，用副牌是"初粘持粘够不够"的问题，用回料是"贴上去翘不翘边"的问题。
巴陵石化：国产SIS规模主力
巴陵石化在湖南岳阳，锂系阴离子聚合基地，SIS牌号体系齐全，线性和星形结构都有，下游标签胶、卫生用品背胶、胶带厂长期供货。央企批次管理规范，S/I比和溶液粘度记录齐全，上海新装置投产后供货更稳。
巴陵SIS副牌料的特点是：国产规模主力，牌号按胶型分档；副牌以溶液粘度和色相小幅偏离为主，适合一般标签胶、双面胶、包装胶和卫生用品背胶掺混。高要求透明胶带和出口卫生用品认证胶仍建议正牌。
适用场景：热熔压敏胶、标签胶、双面胶、卫生巾/纸尿裤背胶、包装胶、塑料沥青改性。
SIS副牌避坑指南
第一，S/I比先对胶型。做初粘型标签胶要低S比，做持粘型要高S比，拿错S/I比，胶一上来初粘持粘就失衡。
第二，溶液粘度要测。涂布工艺按粘度卡，副牌粘度波动大，换料前先小试，别拿错批次直接上涂布线。
第三，初粘持粘要核。压敏胶这两项是核心，副牌先测滚球初粘和持粘时间，掉档的别上标签胶。
第四，透明胶带和出口认证胶别用副牌。高透明胶带和有出口卫生认证要求的胶必须正牌并保留认证，副牌只用于一般标签和包装胶。
科隆仓库现货｜国产SIS压敏胶分批备
科隆在宁波仓库常备国产SIS副牌现货，主推品牌为中石化巴陵石化这一国产SIS主力。主要牌号涵盖YH-1106、YH-1108、YH-4016等线性和星形常用型号，包装分大包装与小包装两种，不同S/I比按胶型分仓码放。
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SIS副牌料到货先抽测S/I比、溶液粘度、初粘持粘三项关键指标，确认胶型可用再签合同；胶厂换料前科隆可先提供小样做涂布和粘接验证，通过后再批量切料。
选型口诀与案例
国产SIS副牌怎么选？记住四句话：S/I比对胶型，粘度要测，初粘持粘要核，透明出口胶不碰副牌。
广州一家做不干胶标签和双面胶的胶厂，原来一直用进口SIS正牌做压敏胶，每吨成本偏高。今年改用科隆供的巴陵石化SIS副牌YH-1106，先拿小样测S/I比和溶液粘度在胶型范围，批量涂布后标签初粘和持粘都达标，成品通过贴标和剥离测试，每吨原料成本降了近一千四百元。老板说：普通标签胶又不是出口卫生背胶，S/I比对、粘度稳，国产副牌完全顶得上。
Throw a set of data: In the hot-melt pressure-sensitive adhesive circle, label adhesive, sanitary pad backing adhesive, and SIS (Styrene-isoprene Styrene Block Copolymer) used for double-sided tape have extremely high domestic supply concentration—Baling Petrochemical alone accounts for the majority of the domestic supply. But products sold under the "SIS sub-brand" on the market fluctuate at first, peel off after pressing during bonding, and the labels curl after just three days of application. SIS's S/I ratio is slightly lower than solution viscosity; initial and long-stick adhesives are two different things. Here are the data; how to choose a secondary label first clarifies the basics of SIS.
Conclusion First: Domestic SIS secondary brands can be used, but the S/I ratio and solution viscosity must first match the rubber type. The main industrialization of SIS in China is Sinopec and Baling Petrochemical. What is
SIS? The domestic thermoplastic rubber
SIS is styrene-isoprene-styrene block copolymer, which is in the same category as SBS but uses isoprene in the middle section. It has low viscosity, good initial adhesion, and is easy to apply. It is the main elastomer for hot melt pressure-sensitive adhesives, widely used for label adhesive, sanitary napkin and diaper backing, double-sided tape, tape, packaging adhesive, and also for plastic and asphalt modification. It is softer and better at initial bonding than SBS, but its heat and oil resistance are average, mainly used in adhesive tape and hygiene products.
Domestic SBS/SBC systems are concentrated in Baling Petrochemical. By industry perspective, Baling Petrochemical (Yueyang, now part of Sinopec's Hunan petrochemical system) has an annual SIS capacity of tens of thousands of tons. The Hunan base is coordinated with Shanghai (with 60,000 tons of SIS to be added in 2025), and grades such as YH-1106, YH-1108, YH-4016 (star-shaped) have been circulating in hot-melt pressure-sensitive rubber rings for years, with complete S/I ratio and linear/star structures. By the perspective of domestic wholly owned main players, Baling Petrochemical is an unavoidable player. Other domestic SIS capacity is still in the early stages and cannot form a stable supply supply.
SIS sub-brand: S/I ratio and solution viscosity are two gates
SIS sub-brands, representing batches within the same original grade system where individual factory inspection indicators slightly deviate. For SIS, the most common differences in secondary brands are concentrated in four items: S/I ratio deviation, fluctuation in solution viscosity, decreased initial tack/retention tackiness, and yellowish hue.
Why are these key points? For SIS hot melt pressure-sensitive adhesives, the S/I ratio determines hardness and adhesion. A higher S-ratio means the adhesive is harder and weaker; a higher I ratio means the adhesive is softer and has poor heat resistance. Solution viscosity determines the coating process and glue amount; incorrect viscosity results in uneven glue application. For label adhesive, initial tack and persistent adhesive are balanced; if the secondary label is off, the label will peel or come off when applied. Difference between
and remix: SIS remix is the reconstruction of glue blocks and edges, which have already undergone a thermal history and deteriorated bonding performance; SIS secondary labels use original factory block particles, with only slight deviations in certain indicators. For label pressure-sensitive adhesive, using secondary labels is a matter of "whether the initial bond holds and sticks sufficiently," while using reuse material is a matter of "whether the edges lift when applied."
Baling Petrochemical: Main domestic SIS production scale
Baling Petrochemical in Yueyang, Hunan, lithium-based anion polymerization base, complete SIS grade system, both linear and star-shaped structures, long-term supply to downstream label adhesive, hygiene product adhesive, and tape factories. Central enterprise batch management standardized, complete S/I ratio and solution viscosity records, stable supply after new Shanghai plant commissioning.
Baling SIS secondary brand material characteristics: domestic scale main product, grades classified by adhesive type; Secondary brand mainly has slight deviations in solution viscosity and hue, suitable for mixing general label adhesive, double-sided tape, packaging adhesive, and hygiene product adhesive. High-demand transparent tape and export hygiene product certification adhesive still recommend genuine brands.
Applicable scenarios: hot-melt pressure-sensitive adhesive, label adhesive, double-sided tape, sanitary napkin/diaper backing, packaging adhesive, plastic asphalt modification.
SIS Secondary Label Pitfall Guide
First, S/I ratio should first match the adhesive type. For initial adhesive label adhesive, use a lower S ratio; for long-stick type, use a higher S ratio. If you use the wrong S/I ratio, the adhesive will become unbalanced as soon as the initial adhesive holds.
Second, measure the viscosity of the solution. For coating processes, follow the viscosity card; if the secondary brand viscosity fluctuates greatly, test it before changing materials; don't take the wrong batch and apply it directly to the coating line.
Third, initial adhesive must be important. Pressure-sensitive adhesive is the core. For secondary brands, first test the initial adhesion and retention time of rolling balls; if the product is uneven, do not apply label adhesive.
Fourth, do not use secondary brands for transparent tape and export certification adhesive. High-transparency tape and adhesives with export hygiene certification requirements must be genuine and certified; secondary labels are only used for general labels and packaging adhesives.
Cologne warehouse stock | Domestic SIS pressure-sensitive adhesive stocked in batches
Cologne maintains domestic SIS sub-brand stock at the Ningbo warehouse, with Sinopec Baling Petrochemical, the main domestic SIS manufacturer. Main grades include YH-1106, YH-1108, YH-4016, and other linear and star-shaped commonly used models. Packaging is divided into large and small packaging, with different S/I ratios stacked by glue type.
Warehouse stock is usually around 5,000 tons: small sub-brand stocks 800-1,000 tons, boxed sub-brand stocks 300-500 tons, large packages/ton stocks 3,500-3,900 tons.
Supply assurance follows a first-test-then-sign approach: each batch of SIS sub-brand material is first tested for S/I ratio, solution viscosity, and initial tack stickiness—three key indicators—to confirm the adhesive type is suitable before signing the contract; Before the rubber factory switches materials, Cologne can provide samples for coating and bonding verification, and after passing, batch cutting proceeds.
Selection Mnemonics and Case Studies
How to choose domestic SIS sub-brands? Remember these four points: S/I comparison of adhesive type, viscosity must be measured, initial adhesion must be core, transparent export glue should not touch secondary brands.
Guangzhou is a glue factory that makes self-adhesive labels and double-sided tape. Previously, they used imported genuine SIS brand for pressure-sensitive glue, which was relatively high per ton. This year, they switched to Baling Petrochemical's secondary brand YH-1106 supplied by Cologne. First, they used samples to measure the S/I ratio and solution viscosity within the gel type. After mass coating, both the initial and long-stick sticks met standards. The finished product passed labeling and peel tests, reducing raw material costs by nearly 1,400 yuan per ton. The boss said: Ordinary label adhesive is not export hygiene adhesive; S/I comparison and stable viscosity are fully comparable to domestic secondary brands
