塑料市场最近有个怪现象：PC正牌价格一路往下走，副牌市场却越来越热闹。有人说国产PC副牌根本不能用，打出来的灯罩发黄、打出来的板材脆裂；也有人说国产PC副牌比进口回料强多了，只要选对厂、验对指标，照样能用。
今天就把鲁西化工、万华化学、中沙（天津）石化这三家国内PC头部企业的副牌门道，一次讲透。
PC是什么？国内产能到了哪一步
PC是聚碳酸酯，特点是透明、抗冲击、耐热、尺寸稳定，是五大工程塑料里综合性能最好的品种之一。PC大量用于电子电器外壳、汽车大灯灯罩、光学镜片、板材、水瓶、奶瓶等对透明和韧性都有要求的制品。
国内PC产能经过近十年扩产，已经从"几乎完全依赖进口"走到"国产为主"。万华化学是国内PC产能最大的本土企业；鲁西化工是国内PC老牌生产企业；中沙（天津）石化是中石化与沙特基础工业公司（SABIC）的合资企业，产能规模较大，属于合资企业，本文作为行业背景一并介绍。此外，科思创（上海）、浙江石化、利华益维远等也是重要PC产能方。
PC副牌：透明和黄变指数是两个硬指标
PC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PC上，副牌最常见的差异点集中在三项：透光率略低、黄变指数（YI）偏高、熔指波动。
为什么这三项关键？PC的核心卖点就是"透明且耐冲击"。透光率差了，灯罩和镜片就发雾；黄变指数高了，制品用几个月就发黄；熔指波动大，薄壁透明件充模不稳定。
和回料的区别再说一遍：PC回料是透明制品破碎再造粒，透光率和抗冲击已经损失很多，黄变严重；PC副牌是原厂原生粒子，只是个别指标小幅偏离。做灯罩，用副牌是"黄变够不够低"的问题，用回料是"能不能透光"的问题。
鲁西化工：国产PC老牌主力
鲁西化工是国内PC老牌生产企业，PC产能约30万吨/年，光气法工艺，在国内PC国产化进程中走得较早。其PC产品覆盖通用级、透明级、阻燃级多个方向，在板材、电子电器、汽车领域有稳定客户。
代表牌号方面，鲁西PC以通用注塑级和挤出级为主。其副牌料的特点是：透明级副牌在透光率上仍有底子，适合对透明要求不极端的板材和罩件；色相偶有偏差，适合深色件或配色件；成本优势突出。
适用场景：PC板材、灯罩、电子电器外壳、日用透明制品、配色件。
万华化学：国产PC产能头部
万华化学是国内PC产能最大的本土企业之一，PC产能约60万吨/年，采用光气法与非光气法双路线布局，产品聚焦汽车、光学、医疗等高端领域。万华PC在差异化产品开发上投入较大，市场价格和差异化水平在国内排在前列。
代表牌号方面，万华PC覆盖光学级、通用级、阻燃级多个方向。其副牌料的特点是：光学级副牌在透光率和黄变指数上底子较好，适合对透明要求较高但不做认证光学件的制品；通用级副牌适合电子电器外壳、汽车内饰件。
适用场景：汽车内饰件、电子电器外壳、光学镜片（非认证件）、灯罩、板材。
中沙（天津）石化：合资企业，行业背景参考
中沙（天津）石化是中国石油化工股份有限公司与沙特基础工业公司（SABIC）的合资企业，PC产能规模较大，在国内PC市场有重要地位。需要说明的是，中沙（天津）石化为合资企业，按"国内=中国大陆本土企业"口径，本文将其作为行业背景参考，不作为国内本土头部企业主推荐。
代表牌号方面，中沙天津PC以通用级和透明级为主，依托SABIC技术背景，产品品质在国产PC里排在前列。其副牌料的特点是：批次稳定性较好，透明级副牌在透光率上有底子；但合资企业副牌流通渠道相对集中，市场货源不如本土企业分散。
适用场景：透明罩件、板材、电子电器外壳、汽车内饰件。
PC副牌避坑指南
第一，透明光学件别拿黄变指数高的副牌。做灯罩、镜片，黄变指数是硬指标，副牌YI高了，制品用几个月就发黄，客户一眼就看出来。
第二，饮水接触件必须用正牌。PC用于水瓶、奶瓶等饮水接触制品，有食品接触认证要求，副牌不具备认证资质，别拿副牌赌。
第三，熔指必须和模具匹配。PC副牌熔指波动比正牌大，薄壁透明件对熔指要求高，选之前先试料。
第四，注意PC必须充分干燥。PC吸潮，注塑前必须120度以上干燥4-6小时，副牌料如果仓储时间长，含水率风险更大，干燥要更充分。
科隆仓库现货｜国产PC三家货源
科隆在宁波仓库常备国产PC副牌现货，主推品牌覆盖鲁西化工、万华化学两家国内本土头部企业，中沙（天津）石化作为合资背景货源按需调配。主要牌号涵盖通用级、透明级、阻燃级多个常用型号，包装分大包装与小包装两种。
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PC副牌料进厂先做透光率、黄变指数、熔指三项快测，指标确认后再签合同放行；批次留样可追溯，检测单随货走。
选型口诀与案例
国产PC副牌怎么选？记住四句话：透明件看黄变，饮水件别用副牌，熔指匹配薄壁件，干燥充分再上机。
无锡一家做PC灯罩的注塑厂，此前一直用某进口PC正牌，每吨成本偏高。今年改用科隆供的万华化学PC副牌通用透明级，先拿两吨小样试机，透光率和黄变指数都在产品接受范围内，批量切料后灯罩装机黄变测试通过，每吨原料成本降了近两千五百元。厂长说：不是认证光学件，副牌黄变够用，为什么要花正牌的钱？
There has been a strange phenomenon in the plastics market recently: the prices of genuine PC keep dropping, while the market for secondary-brand PCs is getting more and more lively. Some people say that domestic secondary-brand PC is basically unusable, producing yellowed lampshades and brittle sheets; others say that domestic secondary-brand PC is much better than imported recycled material, and as long as you choose the right factory and check the right indicators, it can still be used.
Today, we will thoroughly explain the sub-brand strategies of the three leading domestic PC companies: Luxi Chemical, Wanhua Chemical, and Zhongsma (Tianjin) Petrochemical.
What is a PC? What stage has domestic production reached?
PC is polycarbonate, characterized by transparency, impact resistance, heat resistance, and dimensional stability. It is one of the best-performing varieties among the five major engineering plastics. PC is widely used in electronic and electrical housings, automotive headlight covers, optical lenses, sheets, water bottles, baby bottles, and other products that require both transparency and toughness.
After nearly ten years of capacity expansion, domestic PC production has progressed from 'almost entirely dependent on imports' to 'mainly domestic production.' Wanhua Chemical is the largest domestic PC manufacturer; Luxi Chemical is an established domestic PC producer; Sinopec-SABIC (Tianjin) Petrochemical is a joint venture between Sinopec and Saudi Basic Industries Corporation (SABIC) with a relatively large production capacity and is introduced here as industry background. In addition, Covestro (Shanghai), Zhejiang Petrochemical, and Lihuayi Weiyuan are also important PC producers.
PC secondary indicators: transparency and yellowing index are two hard indicators
PC sub-grade refers to batches within the same original factory grade system whose test indicators slightly deviate. When it comes to PC, the most common differences in sub-grades are concentrated in three aspects: slightly lower light transmittance, higher yellowing index (YI), and melt flow fluctuations.
Why are these three aspects critical? The core selling point of PC is 'transparent and impact-resistant.' If the light transmittance is poor, the lampshades and lenses will fog up; if the yellowing index is high, the product will turn yellow after a few months of use; if the melt flow index fluctuates greatly, the molding of thin-walled transparent parts will be unstable.
Let's go over the difference with recycled material again: PC recycled material is made by crushing and re-granulating transparent products, so both light transmittance and impact resistance have deteriorated significantly, and yellowing is severe; PC secondary brand is made from the original manufacturer's virgin pellets, with only slight deviations in certain specifications. When making lampshades, using the secondary brand is a 'whether the yellowing is low enough' issue, while using recycled material is a 'whether it can transmit light' issue.
Luxi Chemical: Veteran Domestic PC Main Player
Luxi Chemical is a long-established domestic PC manufacturer, with a PC production capacity of about 300,000 tons per year, using the phosgene process. It started relatively early in the process of domestic PC localization. Its PC products cover general grade, transparent grade, and flame-retardant grade, and it has stable customers in the fields of sheets, electronics and appliances, and automobiles.
In terms of brand representation, Luxi PC mainly focuses on general-purpose injection molding grade and extrusion grade. The characteristics of its secondary-grade materials are: the transparent grade secondary material still has a foundation in light transmittance, suitable for sheets and covers where extreme transparency is not required; there may be occasional color deviations, suitable for dark-colored parts or color-matched parts; the cost advantage is prominent.
Applicable scenarios: PC sheets, lampshades, electronic and electrical enclosures, daily-use transparent products, color-matching parts.
Wanhua Chemical: Leading domestic PC production capacity
Wanhua Chemical is one of the largest domestic PC producers in China, with an annual PC production capacity of about 600,000 tons. It adopts both the phosgene process and non-phosgene process for production, focusing its products on high-end fields such as automotive, optics, and medical. Wanhua PC invests heavily in the development of differentiated products, with market prices and levels of differentiation ranking among the top domestically.
In terms of brand grades, Wanhua PC covers multiple directions including optical grade, general grade, and flame-retardant grade. The characteristics of its secondary grade materials are: optical grade secondary materials have a relatively good foundation in light transmittance and yellowing index, suitable for products that require high transparency but are not certified as optical components; general grade secondary materials are suitable for electronic and electrical housings, as well as automotive interior parts.
Applicable scenarios: automotive interior parts, electronic and electrical housings, optical lenses (non-certified), lampshades, and panels.
Sino-Saudi (Tianjin) Petrochemical: Joint Venture, Industry Background Reference
Sino-Saudi (Tianjin) Petrochemical is a joint venture between China Petroleum & Chemical Corporation and Saudi Basic Industries Corporation (SABIC). It has a relatively large PC production capacity and holds an important position in the domestic PC market. It should be noted that Sino-Saudi (Tianjin) Petrochemical is a joint venture. According to the notion of "domestic = local mainland Chinese enterprises," this article considers it as a reference for industry background, rather than a main recommendation among leading domestic companies.
In terms of brand representation, Zhongsha Tianjin PC mainly focuses on general-purpose and transparent grades. Relying on SABIC's technical background, the product quality ranks among the top in domestic PC. The characteristics of its secondary brand material are: batch stability is relatively good, and the transparent secondary brand has a solid base in light transmittance; however, the circulation channels of joint venture secondary brands are relatively concentrated, and market supply is not as dispersed as that of local enterprises.
Applicable scenarios: transparent covers, sheets, electronic and electrical housings, automotive interior parts.
PC Side Deck Pitfall Avoidance Guide
First, don't use secondary brands of transparent optical components that have a high yellowing index. For making lampshades and lenses, the yellowing index is a strict criterion. If a secondary brand has a high YI, the product will turn yellow after a few months, and customers will notice it immediately.
Second, water-contact parts must use genuine brands. PC is used for water bottles, baby bottles, and other water-contact products, which require food contact certification. Sub-brands do not have certification qualifications, so don’t gamble with sub-brands.
Third, the melt flow index must match the mold. The melt flow index of PC secondary brands fluctuates more than that of the original brand, and thin-walled transparent parts have high requirements for the melt flow index, so test the material before selection.
Fourth, pay attention that PC must be fully dried. PC absorbs moisture, and before injection molding it must be dried at over 120 degrees for 4-6 hours. For secondary or off-brand materials, if storage time is long, the risk of moisture content is even greater, so drying must be more thorough.
Cologne Warehouse Stock | Domestic PC from Three Suppliers
Cologne keeps regular stock of domestic PC sub-brands at its Ningbo warehouse, mainly promoting brands covering two leading local companies, Luxi Chemical and Wanhua Chemical. Sinopec (Tianjin) Petrochemical, with a joint venture background, provides supplies that can be allocated as needed. The main grades include commonly used types such as general grade, transparent grade, and flame-retardant grade, and the packaging is divided into large and small packages.
The warehouse usually has about 5,000 tons of stock: 800-1,000 tons of small-pack secondary brand stock, 300-500 tons of boxed secondary brand stock, and 3,500-3,900 tons of large-bag/ton-bag stock.
Supply assurance follows the principle of 'test first, sign later': For each batch of PC sub-brand material entering the factory, quick tests for light transmittance, yellowing index, and melt flow index are conducted first, and contracts are signed and released only after the indicators are confirmed; batch samples are retained for traceability, and test reports accompany the goods.
Selection Mnemonics and Case Studies
How to choose a domestic PC sub-brand? Remember four sentences: check if transparent parts yellow, don’t use sub-brands for drinking water parts, match melt flow index with thin-walled parts, and make sure drying is thorough before machine processing.
An injection molding factory for PC lampshades in Wuxi had previously been using a certain imported genuine PC brand, which was relatively expensive per ton. This year, they switched to the generic transparent grade of Wanhua Chemical PC supplied by Kolon. They first tried a two-ton sample for trial, and both the light transmittance and yellowing index were within the acceptable range for the products. After mass batching and processing, the lampshades passed the yellowing test upon assembly, and the cost of raw materials per ton dropped by nearly 2,500 yuan. The factory manager said: 'These are not certified optical parts, and the yellowing of the generic brand is sufficient. Why spend money on the genuine brand?'
