Non-Minera-Oil-Filled: Only the Baseline – What the 50-Year Durability Test Reveals

In our previous installments, we have repeatedly warned about a chronic industry issue: the hazards of oil-filled sealants.

Insulating glass unit oil migration, seal failure, curtain wall glass debonding, silicone sealant hardening and cracking...

These alarming cases consistently reinforce one consensus: oil-filled sealants must be resolutely rejected.

Many clients have thus breathed a sigh of relief:

"As long as I avoid cheap oil-filled sealants, my project should be safe."

But as a technology-driven player with over four decades of deep industry expertise, Baiyun Technology must tell you a harsher truth:
Simply rejecting oil-filled products is far from sufficient.

Even among products that are all "non-oil-filled,"

different brands and different formulations can still exhibit vastly different performance after 5, 10, 25, or even more years.

Some sealants remain as flexible as ever after 25 years;

others harden, become brittle, and suffer significant strength loss within just 3 years.

This underlying gap is the true moat of Baiyun Technology.

Today, we are not talking about the baseline—we are talking about the upper limit.

Let us dive into the deep end of formulation technology and see how a "top-tier long-distance runner" is forged.

In the laboratory, a few hundred hours of accelerated aging testing

may make most products appear "comparable."

But the service life of a building curtain wall spans decades.

In the face of nature, short-term laboratory data can often be deceptive.

It cannot replicate the complex combinations of natural environments, and therefore its results do not correlate with the actual in-service performance of sealants.

Baiyun Technology launched the world's first 50-Year Durability Test for silicone sealants in 1997.

▲ Figure 1 Domestic exposure site for the 50-Year Durability Test

▲ Figure 2 Overseas exposure site for the 50-Year Durability Test

At natural weathering exposure sites, a large number of specimens are subjected day after day to rigorous conditions including UV radiation, extreme temperatures, and rainfall, as shown in Figures 1 and 2.

There is no acceleration here—only the passage of real time.

We have uncovered an alarming fact:
Many products that are indeed non-oil-filled
still exhibit significant performance degradation after 5 to 10 years of service.

Sealants that were once elastic begin to harden and become brittle, losing their sealing and adhesion capabilities.

At best, this leads to building water leakage;

at worst, it poses a serious safety risk of glass falling during typhoons.

To scientifically verify this issue, Baiyun Technology, within the framework of the 50-Year Durability Test,

specifically designed comparative test protocols to conduct long-term, continuous monitoring of sealant performance across different specimens and different environmental conditions.

During this continuous monitoring, the results clearly show that the performance degradation curves of sealants with different formulations differ significantly.

✅ Excellent Formulation (Baiyun Specimen)

Silicone structural sealant specimens with excellent formulations (e.g., Specimen G) were exposed to different climatic conditions (G: Guangdong, O: Indoor, T: Turpan). Their tensile strength and elongation at maximum strength exhibited some variation, but overall remained relatively stable, as shown in Figure 3.

▲ Figure 3 Tensile strength and elongation at maximum strength of Specimen G as a function of aging time

❌ Ordinary Formulation (Other Brands)

For silicone structural sealant specimens with certain other formulations (e.g., Specimens F and H), exposed to the same climatic conditions, a trend of decreasing strength and elasticity was observed, in some cases even falling below national standard requirements, as shown in Figure 4.

▲ Figure 4 Tensile strength and elongation at maximum strength of Specimens F and H as a function of aging time

The above data raise the question:
None of the formulations contain mineral oil, so why is the performance disparity so pronounced?
The answer lies in the depths of formulation technology that most people never see.

Many mistakenly assume that sealant formulation is simply "cooking by recipe"—mixing raw materials in given proportions.

This could not be further from the truth.

Silicone sealant formulation is a complex systems engineering integrating organic chemistry, polymer physics, and rheology.

The gap between top-tier performance and mediocrity stems from deep interplay across the following three dimensions.

Gate One: Base Polymer

The Soul of the Formulation—A Small Deviation Leads to a Vast Difference

Silicone sealant is an elastomer formed by compounding and vulcanizing a linear polyorganosiloxane base polymer (gum) with crosslinkers, reinforcing fillers, and other compounding agents, as illustrated in Figure 5.

Among these, the silicone base polymer is the soul of the sealant formulation system.

▲ Figure 5 Polymer based on polydimethylsiloxane (PDMS)

Ordinary formulation: focuses only on viscosity—as long as the viscosity is adjusted to the right range, that suffices.

Top-tier formulation: delves into the molecular weight distribution curve.

An overly broad molecular weight distribution indicates an excess of low-molecular-weight chains. While this may improve initial extrudability, it compromises long-term mechanical properties and durability. Baiyun Technology precisely controls the polymer's molecular weight distribution to better enhance the mechanical properties and elongation of silicone sealants.

Gate Two: Fillers and Additives

Details Determine Success or Failure; Quantitative Changes Lead to Qualitative Changes

Beyond the silicone base polymer—the soul of the sealant—

other components such as fillers, crosslinkers, and catalysts are also critical in silicone sealants.

Baiyun Technology achieves high performance and exceptional durability through the careful selection and optimized proportioning of fillers and additives.

Gate Three: Precision Processing

Translating Laboratory Formulations into Industrial Products

Even with stringent raw material control and optimized formulation systems, without precision processing, it remains mere armchair strategy.

Process control has a decisive impact on product uniformity and stability:

The same formulation, produced via different manufacturing processes, can yield end products with vastly different performance.

In 2002, Baiyun Technology developed China's first fully automatic continuous production line for silicone sealants with proprietary intellectual property, ensuring consistent product quality from batch to batch.

In Baiyun Technology's technical philosophy,

we are not merely producing a sealant;

we are delivering decades of "certainty."

Our goal is not just to be "non-oil-filled,"

but, through ongoing fundamental research, to achieve and maintain an optimal balance across multiple dimensions—weather resistance, mechanical properties, and workability.

Accelerated aging tests, though rapid,

cannot fully simulate the complexity of the real world (diurnal temperature variations, acid rain components, etc.).

Baiyun's sustained heavy investment in the 50-Year Durability Test stems from our conviction that:

Only real time can validate real formulations.

Our long-term weathering exposure tests

serve as the core tool for continuously screening, validating, and optimizing these "top-tier formulations."

The authentic data we gather gives our building curtain wall projects greater confidence.

When a client receives a Baiyun sealant,

they are not just getting a sealant;

they are receiving a long-term-validated "performance data package."

We ensure that this sealant lies on the "most gradual and most predictable" performance degradation curve.

What we sell is not adhesion at the moment of installation,
but peace of mind for decades to come.

"Non-oil-filled" is the safety baseline—the most fundamental requirement for sealant manufacturers.

But formulation refinement is the ceiling of lasting excellence, and that is where a company's core competitiveness truly lies.

How to further enhance aging resistance and adaptability to extreme environments, all while remaining non-oil-filled, has always been a direction of unremitting effort for Baiyun Technology.

Architecture is frozen music,

and sealants are those inconspicuous yet essential rests in the score.

They are not conspicuous, but they determine whether the symphony can endure in harmony.

Baiyun Technology refuses to rest in the comfort zone of "non-oil-filled."

We will continue to explore the uncharted territory of formulation technology, leveraging deep chemical expertise and a long-termist commitment to continually push the limits of silicone sealant performance and service life.