每年冬天，都有一批做再生PP制品的老板睡不踏实。
不是没订单，是货出了问题：周转箱裂了、托盘脆了、白件发黄了、蓝件色差了。
这些翻车，九成都能在选料时提前躲开——只要你读懂再生PP的性能和颜色。
这篇不堆参数，只讲怎么用参数避坑。
性能盯五项：熔指、拉伸、冲击、弯曲模量、灰分；颜色盯一套：国标代码加行业习惯。
参数不是拿来背的，是拿来对号入座的：你的产品什么要求，就找什么参数的料。
熔指是脾气，灰分是底细
熔指（MFR）决定这料能干什么：拉丝级2-4，做编织袋、打包带；注塑级8-15，做周转箱、日用品、家电壳；无纺布级20-40，做纸尿裤、口罩；高熔指纺丝级30-60，上高速纺。
灰分决定这料有多纯：一级≤1%，二级≤3%，三级≤10%。灰分高，要么填料多，要么杂质多，颜色也救不回来。
看料先看这两个数，别的都是后话。
冲击强度不够，冬天就给你脸色看
再生PP的冲击强度，是它和原生料拉开差距的地方。
回收过程分子链会降解，常温缺口冲击一般2-5kJ/m²，遇到低温直接腰斩，冬天一冷，周转箱脆得像饼干。
要救也简单：共混增韧，POE、EPDM都是熟面孔，常温冲击翻倍不是难事；或者直接买高抗冲牌号，冲击能到6-15。
记住一句话：做冬季户外件，冲击强度是底线，不是加分项。
黑色料是遮羞布，也是大生意
再生PP的颜色，就是一张定价表。
黑色B1用量占大头，托盘、垃圾桶、汽车非外观件，全靠它把杂色盖住；蓝色B2做物流周转箱，绿色G2做果筐，灰色G1做汽车件和管材；白色和本色N是香饽饽，做家电壳、瓶盖，靠高纯度分选撑身价；杂色X只能做低端深色件。
颜色翻车是重灾区：嘉兴有家做蓝色塑料托盘的厂，换了一批料后色差忽蓝忽绿，客户验收一批拒一批。后来让宁波市科隆新材料有限公司做配色和批次稳定，科隆的东南亚进口链路成熟，越南、泰国、马来西亚多国备货充足，色差ΔE控制在1.5以内，退货率从8%降到0.5%以下。
你品，颜色看着是小事，翻起车来都是钱。
气味等级4级，客户捂鼻就走
再生PP的气味，是隐藏的退货杀手。
油污、标签胶、降解产物没处理干净，一开箱就是一股味，注塑车间都能闻到，做食品接触件更是直接出局。
行业里气味分等级，国标要求无特定要求时≤4级，车规件要≤3级甚至更低。要达标，靠的是脱挥工艺和除味助剂，不是喷香水。
验货时别光看外观，开袋闻一下，能帮你挡掉一半的坑。
颜色和应用是一对CP
颜色和应用对应关系基本固定：
黑色件：托盘、垃圾桶、汽车底盘件、管材，量大价低；
蓝色件：物流周转箱、整理箱，看色差；
绿色件：果筐、园艺盆，耐晒优先；
白色件：家电外壳、日用品，纯度优先；
本色件：拉丝、片材、食品级料，干净优先。
记住这个对应表，选色和选料可以一步到位。
写在最后：五查口诀，验收再生PP
1. 查熔指：和工艺对得上，别差太远；
2. 查灰分：越低越值钱，一级≤1%；
3. 查冲击：冬季户外件，底线先卡住；
4. 查气味：开袋闻一闻，4级以上要警惕；
5. 查色差：同一批次ΔE超过2，退货风险大增。
写在最后：再生PP的性能和颜色，说到底就是"纯净度"两个字——料越纯，性能越稳，颜色越正。宁波市科隆新材料有限公司常年处理再生PP的性能达标和颜色稳定问题，说白了，就是让每一批料都经得起检验。
Every winter, there's a group of business owners making recycled PP products who can't sleep soundly.
It's not that there are no orders, it's that the goods have problems: the turnover box is cracked, the pallet is brittle, the white parts are yellowing, and the blue parts are color-poor.
These mishaps can probably be avoided in advance when selecting materials—as long as you understand the performance and color of recycled PP.
This article doesn't pile up parameters, just talk about how to use them to avoid pitfalls.
Performance focuses on five items: melting finger, tensile, impact, bending modulus, ash content; Focusing on color is a set: national standard codes plus industry habits.
Parameters aren't meant to be memorized, but for consistency: look for materials with parameters that meet your product's requirements.
Melting Finger is temperament, ash content is the fineness
Melting Finger (MFR) determines what this material can be used for: Drawing grade 2-4, for woven bags and strapping tape; Injection molding grade 8-15, for turnover boxes, daily necessities, and appliance shells; Non-woven grade 20-40, for diapers and masks; High melting finger spinning grade 30-60, for high-speed spinning.
Ash content determines how pure the material is: Grade 1 ≤1%, Grade 2 ≤3%, Grade 3 ≤10%. High ash content means either more filler or impurities, and the color can't be restored.
Look at these two numbers first; everything else is a matter for later.
If the impact strength isn't strong enough, you'll be at a loss in winter
The impact strength of recycled PP is where it sets it apart from virgin materials.
During recycling, molecular chains degrade; at room temperature, gap impact is generally 2-5 kJ/m², but in low temperatures, it halves in half. In winter, when it gets cold, the recycling box becomes as fragile as biscuits.
Saving is simple: blending toughening, POE and EPDM are familiar names, doubling impact at room temperature is not difficult; Or just buy a high impact resistance grade, which can reach 6-15 degrees.
Remember this say: when making winter outdoor gear, impact strength is the bottom line, not a bonus.
Black material is a fig leaf and a big business
The color of recycled PP is basically a pricing list.
Black B1 accounts for the majority of usage, covering pallets, trash bins, and non-exterior automotive parts; Blue B2 is used for logistics turnover boxes, green G2 for fruit baskets, and gray G1 for automotive parts and pipes; White and natural color N are highly sought after, used for appliance shells and bottle caps, supported by high-purity sorting; Mixed color X can only be used for low-end dark-colored parts.
Color failures are the hardest hit: In Jiaxing, a factory making blue plastic pallets switched to a batch of material, causing color differences to fluctuate between blue and green, and customers rejected every batch. Later, Ningbo Kelong New Materials Co., Ltd. handled color matching and batch stabilization. Cologne's Southeast Asian import chain was mature, with ample stock in Vietnam, Thailand, Malaysia, and other countries. Color difference ΔE was controlled below 1.5, and the return rate dropped from 8% to below 0.5%.
You Taste it, color may seem like a minor issue, but if it flips, it's all money.
Odor level 4, customers just cover their noses and leave
The smell of recycled PP is a hidden return killer.
Oil stains, label glue, and degradation products aren't properly handled; as soon as you open the box, there's a strong smell that can be smelled in injection molding workshops, and making food contact parts is even more of a hit.
In the industry, odors are graded. If the national standard doesn't specify a ≤ level, it's level 4, and automotive-grade parts need ≤ grade 3 or even lower. To meet the standards, you rely on the devoltilization process and deodorizing agents, not perfume.
Don't just look at the appearance when inspecting—opening the bag and smelling it can help you avoid half the pitfall.
Color and application are a pair.
Color and application basically have a fixed relationship:
Black parts: pallets, trash bins, car chassis parts, pipes, large quantity, low price;
Blue parts: logistics turnover boxes, organizing boxes, check color differences;
Green items: fruit baskets, gardening pots, prioritizing sun resistance;
White items: home appliance shells, daily necessities, purity priority;
Natural color items: brushed, sheet, food-grade materials, cleanliness first.
Remember this corresponding chart to select colors and materials in one step.
Final note: Five-check mnemonic, accept recycled PP
1. Check melting index: match the process, don't miss too much;
2. Check ash content: the lower the ash content, the more valuable it is, grade 1 ≤1%;
3. Check for impact: For winter outdoor items, the bottom line is set first;
4. Check for odor: open the bag and smell it; be cautious of levels above level 4;
5. Check for color difference: If the same batch exceeds ΔE 2, the risk of returns increases significantly.
In conclusion: The performance and color of recycled PP ultimately come down to "purity"—the purer the material, the more stable the performance and the more accurate the color. Ningbo Kelong New Materials Co., Ltd. has long handled the performance standards and color stability issues of recycled PP, essentially ensuring every batch can withstand inspection
