认知错位：便宜的PVC副牌，往往卡在杂质和热稳定上
很多人以为PVC副牌便宜是因为纯度不够，其实不完全是。成都一家做PVC型材和管材的厂，收过一批低价PVC副牌，外观看着没毛病，可一上机加工，颜色发黄、分解冒烟，成品强度也掉了。一查，问题不在纯度，在杂质和热稳定性——混了不稳定的批次，加工温度一上去就分解。国产PVC副牌到底怎么验？中泰化学、新疆天业、君正集团，这三家是主流货源，这篇横评给你答案。
国产PVC格局：西北电石法三家领跑
PVC（聚氯乙烯）耐腐蚀、阻燃、力学性能好，做型材、管材、管材管件、异型材都离不开。国内PVC产能约3000万吨/年，是氯碱化工的大品类，产能集中在西北电石法路线。
中泰化学（新疆中泰化学）PVC产能约215万至260万吨/年，依托新疆电石、石灰石和自备电厂，是国内PVC产能规模领先的企业；新疆天业依托新疆石河子，PVC产能约130万至198万吨/年，电石法和乙烯法都有；君正集团（内蒙古君正）PVC产能约140万至186万吨/年，内蒙古乌海电石法路线。这三家，构成了国产PVC的主流货源。
PVC副牌：电石法料的杂质和热稳定是两道坎
PVC副牌的概念和其他塑料一致：同一装置同一牌号，出厂检验个别指标——黏数（K值）、热稳定性、杂质含量、色相——小幅偏离正牌标准。来源是开停车头尾料、牌号切换过渡料、工艺波动批次。仍是原生聚合粒子。
PVC副牌有个特殊性：电石法路线的料，杂质和热稳定性是两道坎。PVC加工温度接近分解温度，热稳定性不够，一加工就发黄分解。副牌容易出问题的就是热稳定性和杂质。分清四层：正牌全指标达标；副牌基材一致、个别指标略偏；回料受过一次热历史；再生料性能波动大。PVC副牌价格通常低于正牌，做型材、管材、一般异型材这类场景用副牌，关键是把热稳定性测住。
中泰化学PVC：新疆电石法龙头，SG-5走量
中泰化学是国内PVC产能规模领先的企业，依托新疆电石、石灰石和自备电厂，氯碱循环经济完整。代表牌号如SG-5是电石法通用料，SG-3也有稳定市场。
中泰PVC副牌的特点，是电石法装置规模化，副牌主要来自过渡料和波动批次。SG-5这类通用料走量大，副牌货源相对充裕。适合做型材、管材、一般异型材。要注意的是，电石法料进厂先测热稳定性和杂质，加工温度别卡太死。
新疆天业PVC：石河子基地，氯碱一体化
新疆天业依托石河子基地，PVC产能约130万至198万吨/年，电石法和乙烯法都有，氯碱一体化配套。代表牌号如SG-5等。
天业PVC副牌的特点，是基地一体化配套，副牌货源以通用料过渡批次为主。适合型材、管材、一般异型材。因为新疆成本有优势，它的副牌价格带往往有竞争力。要注意的是，电石法和乙烯法料要分清，加工工艺略有差异。
君正集团PVC：内蒙古乌海，电石法成本低
君正集团（内蒙古君正）依托乌海，PVC产能约140万至186万吨/年，电石法路线。代表牌号如SG-5等。
君正PVC副牌的特点，是内蒙古电石法成本低，副牌集中在通用料过渡批次。适合型材、管材、一般异型材。因为原料成本低，它的副牌价格带往往有竞争力。要注意的是，电石法料进厂先测热稳定性。
国产PVC副牌怎么验，留样可溯才不翻车
一是先测热稳定性。PVC副牌容易出问题的就是热稳定性，进厂先做热稳定性测试，对照自己加工温度。二是，先测杂质和色相。电石法料杂质要单独测。三是，批次留样可溯。单批副牌量小，留样备查。成都那个厂的教训，就是没测热稳定性，一加工就分解。
科隆仓库现货｜国产PVC留样可溯
做国产PVC副牌，留样可溯才不翻车。科隆仓库常备国产PVC现货，主推中泰化学、新疆天业、君正集团三家品牌。
• 主推品牌：中泰化学、新疆天业、君正集团
• 主要牌号：SG-5、SG-3等常用牌号
• 包装规格：大包装、小包装都有
• 仓库现货：通常在2000-5000吨
• 小包副牌备货300-600吨、箱装副牌备货150-300吨、大包料/吨包料备货1500-4100吨
• 供应保障：批次留样可溯
大包料、吨包料适合连续生产的型材和管材厂，小包副牌和箱装副牌适合中小厂试机和补单，按需调度。
选型口诀加一个真实案例
国产PVC副牌选型，记住三句话：先测热稳定、杂质色相单测、批次留样。别光看报价，把热稳定性测住了，省下来的才是真钱。
说成都那个厂。后来他们改用中泰化学SG-5副牌做型材，进厂先测热稳定性，数据在加工窗口内；杂质和色相也在可接受范围。上机加工，颜色发黄和分解冒烟的问题都没再出现，成品强度测试和正牌做的没明显差距，单吨成本比正牌降了约350元。差别不在料多神，而在测了热稳定性、留了样。
Misunderstanding: Cheap PVC sub-brands often get stuck in impurities and thermal stability
Many people think PVC sub-brands are cheap because of insufficient purity, but that's not entirely true. A factory in Chengdu specializing in PVC profiles and pipes once received a batch of low-priced PVC sub-brands. They looked fine on the outside, but once machined, the color turned yellow, decomposed, and smoked, and the finished product's strength dropped. Upon inspection, the problem wasn't purity, but impurities and thermal stability—mixing unstable batches would decompose as soon as the processing temperature rose. How exactly do domestic PVC sub-brands inspect? Zhongtai Chemical, Xinjiang Tianye, and Junzheng Group are the main sources of goods. This review gives you the answer.
Domestic PVC Landscape: The three leading companies in the Northwest Calcium Carbide method (PVC)
PVC (polyvinyl chloride) have good corrosion resistance, flame retardancy, and mechanical properties, making profiles, pipes, fittings, and profiles indispensable. Domestic PVC production capacity is about 30 million tons per year, making it a major category in chlor-alkali chemicals, with capacity concentrated in the Northwest Calcium Carbide process.
Zhongtai Chemical (Xinjiang Zhongtai Chemical) has a PVC production capacity of about 2.15 million to 2.6 million tons per year, relying on Xinjiang calcium carbide, limestone, and self-owned power plants, making it a leading domestic PVC production capacity; Xinjiang Tianye relies on Xinjiang Shihezi, with PVC capacity of about 1.3 million to 1.98 million tons/year, including both carbide and ethylene processes; Junzheng Group (Inner Mongolia Junzheng) has a PVC production capacity of about 1.4 to 1.86 million tons per year, following the Inner Mongolia Wuhai carbide process. These three companies form the mainstream supply sources for domestic PVC.
PVC sub-brand: Impurities and thermal stability of calcium carbide materials are two key hurdles
PVC The concept of sub-brands is consistent with other plastics: same device and grade, factory inspection of individual indicators—viscosity (K value), thermal stability, impurity content, hue—slightly deviate from genuine brand standards. Sources include start-stop and start-up materials, grade switching transition materials, and process fluctuation batches. Still primary polymer particles.
PVC sub-brand has a special feature: materials from the calcium carbide process have two hurdles: impurities and thermal stability are two hurdles. PVC processing temperature is close to decomposition temperature, but thermal stability is insufficient, and it turns yellow and decomposes upon processing. Sub-brand products are prone to problems mainly with thermal stability and impurities. Four clear layers: genuine brand meets all indicators; Sub-brand base material is consistent, with some indicators slightly off; Repost material has undergone one thermal history; Recycled material has large performance fluctuations. PVC sub-brand prices are usually lower than genuine brands. For profiles, pipes, and general profiles, sub-brands are used, with the key being to measure thermal stability.
Zhongtai Chemical PVC: Xinjiang's leader in carbide processing, SG-5 sales
Zhongtai Chemical is a leading domestic PVC production capacity, relying on Xinjiang calcium carbide, limestone, and self-owned power plants, with a complete chlor-alkali circular economy. Representative grades include SG-5, which is a general material for the calcium carbide process, and SG-3 also has a stable market. The characteristic of
Zhongtai PVC's secondary brand is the large-scale carbide process, with secondary brands mainly coming from transition materials and fluctuating batches. General materials like SG-5 have large volumes, and secondary brand supply is relatively abundant. Suitable for making profiles, pipes, and general special-profile materials. It is important to note that calcium carbide material must first be tested for thermal stability and impurities upon arrival, and the processing temperature should not be too rigid.
Xinjiang Tianye PVC: Shihezi base, chlor-alkali integration
Xinjiang Tianye relies on the Shihezi base, PVC production capacity is about 1.3 million to 1.98 million tons/year, with both carbide and ethylene processes, supporting chlor-alkali integration. Representative grades include SG-5 and others. The characteristic of
Tianye PVC sub-brand is that it is integrated with the base, with sub-brand supply mainly consisting of general material transition batches. It is suitable for profiles, pipes, and general special profiles. Because Xinjiang has cost advantages, its sub-brand price range is often competitive. It should be noted that calcium carbide and ethylene materials must be clearly distinguished, with slight differences in processing technology.
Junzheng Group PVC: Wuhai, Inner Mongolia, with low calcium carbide process costs
Junzheng Group (Inner Mongolia Junzheng) relying on Wuhai, PVC production capacity of about 1.4 million to 1.86 million tons/year, following the calcium carbide process route. Representative grades include SG-5 and others. The characteristic of
Junzheng PVC sub-brand is that the calcium carbide process in Inner Mongolia has low costs, with sub-brands concentrated in the general material transition batch. Suitable for profiles, pipes, and general profiles. Because raw material costs are low, its sub-brand prices are often competitive. Note that calcium carbide material must first be tested for thermal stability upon arrival.
How to inspect domestic PVC sub-brands? Traceable samples to avoid mistakes
First, test thermal stability. The main issue with PVC sub-brands is thermal stability. Upon arrival, conduct thermal stability tests and compare to your processing temperature. Second, first test impurities and hue. Impurities in calcium carbide materials must be tested separately. Third, batch samples can be traced. Small quantities per batch are kept for inspection. The lesson from the Chengdu factory was that without measuring thermal stability, it decomposes as soon as processing occurs.
Cologne warehouse stock | Traceable domestic PVC samples
Domestic PVC secondary brand, traceable samples ensure no mishaps. Cologne warehouse always stocks domestic PVC stock, mainly promoting Zhongtai Chemical, Xinjiang Tianye, and Junzheng Group brands.
• Main Brands: Zhongtai Chemical, Xinjiang Tianye, Junzheng Group
• Main Grades: SG-5, SG-3, and other commonly used grades
• Packaging Specifications: Both large and small packages available
• Warehouse Stock: Usually between 2000-5000 tons
• Small sub-brand stock 300-600 tons, container sub-brand stock 150-300 tons, large package/ton sub-brand stock 1500-4100 tons
• Supply Guarantee: Batch samples traceable
Large package materials and ton packages are suitable for continuous production profile and pipe factories; small package sub-brands and boxed sub-brands are suitable for small and medium factories to test machines and supplement orders, with dispatch as needed.
Selection Mnemonic, a real case
Domestic PVC sub-brand selection, remember these three points: first test thermal stability, test impurity hue separately, and keep samples for batches. Don't just look at the quote—once you measure thermal stability, the real money you save is what you save.
Talking about that factory in Chengdu. Later, they switched to using Zhongtai Chemical's SG-5 sub-brand for profiles, first testing thermal stability upon entry, with data in the processing window; Impurities and hue were also within acceptable ranges. After machine processing, issues like yellowing of color and decomposition and smoke no longer occurred, and the finished product strength test showed no significant difference compared to genuine products. The cost per ton was about 350 yuan lower than the genuine brand. The difference wasn't in the amount of material but in thermal stability and sample retention
