老徐在苏州做卫生用品背胶，仓里那几托D1161的SIS在托盘上放了快大半年。一个纸尿裤大客户换了热熔胶供应商，库存的SIS颗粒一下子多出来七八吨。袋口有点吸潮，粒子表面发暗，仓管翻台账一算，这料单价不算便宜，光资金占用加仓位费一个月小四千。老徐蹲在磅房门口算账：SIS放久了异戊二烯段老化，粘性一掉，做出来的背胶一撕就开，客户要退货。
呆滞料不是资产，是趴在账上的负债。
SIS这东西，做热熔胶、卫生用品胶带、保护膜的老板才熟。它粘性强、浸润好，但怕热怕氧化，夏天仓库没空调，粒子放俩月表面就慢慢变颜色。更麻烦的是它分通用级和高粘级，分子量分布不一样，贩子收料根本不分，一吨当一吨压。SIS放久了跟蜂蜜结晶一样，看着还是那罐蜜，搅不开那个粘劲儿了。你以为放着还能凑合用，其实粘度指标已经悄悄跑偏。
回收的本质，不是卖废料，是把死钱变成活钱。
说个真事。有个老板喊来统货商，对方捏起一粒SIS闻了闻，说有油耗味、老化了，直接按地板价收。统货商的报价单跟天气预报一样——出门前看一眼就行，别当真。他收回去掺进低档热熔胶里，粘性不够就加点增粘树脂补，做出来的胶拿去封纸箱够用，差价全进他口袋。你品品，他不是在收你的废料，是在拿你的贵料去填他的便宜货。有些贩子更损，连牌号都不看，D1161和杂牌SIS混着装一车。
统货商不是在帮你处理废料，是在拿你的好料贴补他的差料。
科隆新材走的是终端消化这条路。我们手里长期有做热熔胶、卫生用品、标签胶的下游客户，像D1161、YH-1105这种流通量大的牌号，收进来对得上客户配方，直接走货不压库。碰到批次偏一点的，能进我们自己的改性配方体系里消化掉，不挑牌号、不挑批次。定价按苯乙烯含量、粘度、氧化程度分级，一级一价，明码写在回收单上。背后有自有产能和客户托底，报价稳，不随行情大起大落。
好料不怕没人收，怕的是你把好料当废料卖了。
上门评估那天，我们技术员带一把硬度计和一支闻味的鼻子——真的，SIS氧化不氧化，一闻就知。现场看是否出油、测粘度，高粘级和通用级分开记。你在场看着过磅，皮重毛重净重三单对得上，不存在到手再砍一刀。
换个玩法更划算——回收料换新料。流程五步：先报料，拍个照、报牌号、吨数、城市；我们上门分级评估，测完当场报价；现场过磅收货；回收款直接抵扣你向科隆采购新料的货款；收尾结算开票。某家做标签胶的老客户，仓里压了大概5吨SIS呆滞料，按分级抵了近一半新料货款，算下来省了约2万多现金流，新拉回来的正是QUANICE全系列弹性体，直接上产线续单。
说白了，废料不是不能要，是看你用什么姿势处理。
具体到牌号，我们常年回收科腾D1161、D1114、D1163PT，巴陵石化YH-1105、YH-1106、YH-1209等主流SIS牌号；台橡、山东聚圣、李长荣等其他厂家牌号以实物评估为准。可回收形态包括呆滞原包料（整托或散包）、挤出浇口料、造粒机头料、试机料、库存尾料。氧化变色的粒子要单独筛出来，别跟新粒混一袋。
说个实在的，SIS放久了氧化变粘，跟茶放久了跑香一样，闻着还是那个味，用起来不是那个劲。趁粘度指标还在线，找个有胶黏剂终端的人接走，比你在仓里跟它耗强。
临了唠两句避坑。回收就是贱卖？真相是分牌号分级卖，好料能卖好价。放着等涨价？真相是SIS放着只会氧化变粘，放越久越不值钱。谁出价高卖谁？真相是到手砍价、压秤、拖款的，价比三家还亏。
Old Xu is doing sanitary product adhesive in Suzhou. The D1161 SIS pallets in the warehouse have been sitting on trays for almost half a year. A major diaper client switched to hot melt glue suppliers, and the inventory of SIS pellets suddenly increased by seven or eight tons. The bag mouth was a bit damp, the pellet surface darkened, and the warehouse manager checked the ledger and found the unit price wasn't cheap—just the capital and position fees alone cost nearly 4,000 yuan a month. Old Xu squatted at the weighbridge door doing the accounts: the isoprene segments aged from sitting long, lost stickiness, and the glue peeled off easily, so the customer wanted to return the product.
Obsolete material isn't an asset, it's a liability lying on the books.
SIS this stuff, only the boss who makes hot melt adhesives, hygiene tapes, and protective films knows the best. It has strong viscosity and good absorption, but it's sensitive to heat and oxidation. In summer, warehouses have no air conditioning, and pellets slowly change color after two months. What's more troublesome is that they are divided into general-purpose and high-viscosity grades, with different molecular weight distributions. Vendors don't even distinguish between them—one ton is worth a ton per ton. When SIS is stored for a long time, it looks like honey crystals—still the same jar of honey, but the stickiness can't be broken anymore. You might think it's okay just sitting there, but the viscosity indicator has quietly deviated.
The essence of recycling isn't selling scrap, but turning dead money into living money.
Let me tell a real story. A boss called in a wholesaler, who picked up a SIS capsule, sniffed it, said it smelled like fuel consumption and was old, and immediately charged at floor price. The wholesaler's quotation sheet is like a weather forecast—just glance at it before you leave, don't take it seriously. They collect it and mix it into low-grade hot melt glue; if the adhesion isn't strong enough, add some tackifying resin to patch it. The glue is enough to seal the cartons, and the price difference goes straight into their pocket. Honestly, they're not collecting your scrap, they're using your expensive materials to fill in their cheap goods. Some dealers are even more ruthless, not even checking the grade, mixing D1161 with generic SIS to fill the whole truckload.
Wholesalers aren't helping you deal with scrap; they're using your good materials to make up for their subpar parts.
Kelong New Materials is taking the path of terminal digestion. We have long-term downstream customers specializing in hot melt adhesives, hygiene products, and label adhesives. For high-circulation grades like D1161 and YH-1105, we buy them that match the customer's formula and sell directly without inventory pressure. If the batch is slightly off, it can be processed into our own modified formula system, regardless of grade or batch. Pricing is graded by styrene content, viscosity, and oxidation level, with one price per grade, clearly written on the recycling form. With our own production capacity and customer backing, our quotes are stable and don't fluctuate wildly with market trends.
Good material isn't afraid of not being picked up; what matters is selling good material as scrap.
On the day of the on-site evaluation, our technician brought a hardness tester and a nose that smelled it—really, whether SIS oxidizes or not, you can tell at a glance. Check for oil release and viscosity on site; record high-tack and general-purpose grades separately. You watch the weighing, and if the tare weight, gross weight, and net weight match, there's no need to cut it off once you get it.
Try a different approach for better value—swap recycled materials for new ones. Five-step process: First, submit materials, take photos, announce grade, tonnage, and city; We go to the site for grading and evaluation, and quote on the spot after measurement; On-site weighing; Payment for recycling directly offsets your purchase of new material from Cologne; Final settlement and invoice issuance. A long-term customer of label glue had about 5 tons of obsolete SIS material stored in the warehouse. By grading, nearly half of the new material payment was offset, saving over 20,000 yuan in cash flow. The new product brought back was the full range of QUANICE elastomers, which were directly added to the production line for renewal.
To put it bluntly, waste isn't something you can't accept; it depends on how you handle it.
As for specific grades, we regularly recycle mainstream SIS grades like Keten D1161, D1114, D1163PT, Baling Petrochemical YH-1105, YH-1106, YH-1209; Other manufacturers like Taiwan Rubber Corporation, Shandong Jusheng, and Li Changrong have grades based on physical appraisal. Recyclable forms include stagnant original pack material (whole or bulk pack), extrusion gate feed, pelletizer head material, test machine feed, and inventory tail material. Oxidized and discolored particles must be screened separately; do not mix them with new pellets in the same bag.
To be honest, SIS oxidizes and sticks over time, just like tea loses its aroma after prolonged storage—it still smells the same, but not as good to use. While the viscosity index is still working, find someone with an adhesive terminal to pick it up and take it away—it's better than just sitting in the warehouse and dealing with it.
Say a few words at the last minute to avoid pitfalls. Is recycling just selling cheap? The truth is, you sell by grade and grade—good materials can sell at good prices. Waiting for prices to rise? The truth is, SIS will only oxidize and become sticky when sold, and the longer you sit it, the less valuable it becomes. Whoever offers the higher price sells it? The truth is, when you get it, you bargain, weigh it, and delay payment—the price is even worse than the other three
